{@code Class} has no public constructor. Instead {@code Class}
* objects are constructed automatically by the Java Virtual Machine as classes
* are loaded and by calls to the {@code defineClass} method in the class
* loader.
*
*
The following example uses a {@code Class} object to print the
* class name of an object:
*
*
* void printClassName(Object obj) {
* System.out.println("The class of " + obj +
* " is " + obj.getClass().getName());
* }
*
It is also possible to get the {@code Class} object for a named
* type (or for void) using a class literal. See Section 15.8.2 of
* The Java™ Language Specification.
* For example:
*
*
* {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
*
* {@code Class.forName(className, true, currentLoader)}
*
For example, the following code fragment returns the
* runtime {@code Class} descriptor for the class named
* {@code java.lang.Thread}:
*
*
* {@code Class t = Class.forName("java.lang.Thread")}
*
* A call to {@code forName("X")} causes the class named
* {@code X} to be initialized.
*
* @param className the fully qualified name of the desired class.
* @return the {@code Class} object for the class with the
* specified name.
* @exception LinkageError if the linkage fails
* @exception ExceptionInInitializerError if the initialization provoked
* by this method fails
* @exception ClassNotFoundException if the class cannot be located
*/
@CallerSensitive
public static Class forName(String className)
throws ClassNotFoundException {
Class caller = Reflection.getCallerClass();
return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
}
/**
* Returns the {@code Class} object associated with the class or
* interface with the given string name, using the given class loader.
* Given the fully qualified name for a class or interface (in the same
* format returned by {@code getName}) this method attempts to
* locate, load, and link the class or interface. The specified class
* loader is used to load the class or interface. If the parameter
* {@code loader} is null, the class is loaded through the bootstrap
* class loader. The class is initialized only if the
* {@code initialize} parameter is {@code true} and if it has
* not been initialized earlier.
*
*
If {@code name} denotes a primitive type or void, an attempt
* will be made to locate a user-defined class in the unnamed package whose
* name is {@code name}. Therefore, this method cannot be used to
* obtain any of the {@code Class} objects representing primitive
* types or void.
*
*
If {@code name} denotes an array class, the component type of
* the array class is loaded but not initialized.
*
*
For example, in an instance method the expression:
*
*
* {@code Class.forName("Foo")}
*
* {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
*
If the {@code loader} is {@code null}, and a security
* manager is present, and the caller's class loader is not null, then this
* method calls the security manager's {@code checkPermission} method
* with a {@code RuntimePermission("getClassLoader")} permission to
* ensure it's ok to access the bootstrap class loader.
*
* @param name fully qualified name of the desired class
* @param initialize whether the class must be initialized
* @param loader class loader from which the class must be loaded
* @return class object representing the desired class
*
* @exception LinkageError if the linkage fails
* @exception ExceptionInInitializerError if the initialization provoked
* by this method fails
* @exception ClassNotFoundException if the class cannot be located by
* the specified class loader
*
* @see java.lang.Class#forName(String)
* @see java.lang.ClassLoader
* @since 1.2
*/
@CallerSensitive
public static Class forName(String name, boolean initialize,
ClassLoader loader)
throws ClassNotFoundException
{
Class caller = null;
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
// Reflective call to get caller class is only needed if a security manager
// is present. Avoid the overhead of making this call otherwise.
caller = Reflection.getCallerClass();
if (loader == null) {
ClassLoader ccl = ClassLoader.getClassLoader(caller);
if (ccl != null) {
sm.checkPermission(
SecurityConstants.GET_CLASSLOADER_PERMISSION);
}
}
}
return forName0(name, initialize, loader, caller);
}
/** Called after security check for system loader access checks have been made. */
private static native Class forName0(String name, boolean initialize,
ClassLoader loader,
Class caller)
throws ClassNotFoundException;
/**
* Creates a new instance of the class represented by this {@code Class}
* object. The class is instantiated as if by a {@code new}
* expression with an empty argument list. The class is initialized if it
* has not already been initialized.
*
*
Note that this method propagates any exception thrown by the
* nullary constructor, including a checked exception. Use of
* this method effectively bypasses the compile-time exception
* checking that would otherwise be performed by the compiler.
* The {@link
* java.lang.reflect.Constructor#newInstance(java.lang.Object...)
* Constructor.newInstance} method avoids this problem by wrapping
* any exception thrown by the constructor in a (checked) {@link
* java.lang.reflect.InvocationTargetException}.
*
* @return a newly allocated instance of the class represented by this
* object.
* @exception IllegalAccessException if the class or its nullary
* constructor is not accessible.
* @exception InstantiationException
* if this {@code Class} represents an abstract class,
* an interface, an array class, a primitive type, or void;
* or if the class has no nullary constructor;
* or if the instantiation fails for some other reason.
* @exception ExceptionInInitializerError if the initialization
* provoked by this method fails.
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
Specifically, if this {@code Class} object represents a
* declared class, this method returns {@code true} if the specified
* {@code Object} argument is an instance of the represented class (or
* of any of its subclasses); it returns {@code false} otherwise. If
* this {@code Class} object represents an array class, this method
* returns {@code true} if the specified {@code Object} argument
* can be converted to an object of the array class by an identity
* conversion or by a widening reference conversion; it returns
* {@code false} otherwise. If this {@code Class} object
* represents an interface, this method returns {@code true} if the
* class or any superclass of the specified {@code Object} argument
* implements this interface; it returns {@code false} otherwise. If
* this {@code Class} object represents a primitive type, this method
* returns {@code false}.
*
* @param obj the object to check
* @return true if {@code obj} is an instance of this class
*
* @since JDK1.1
*/
public native boolean isInstance(Object obj);
/**
* Determines if the class or interface represented by this
* {@code Class} object is either the same as, or is a superclass or
* superinterface of, the class or interface represented by the specified
* {@code Class} parameter. It returns {@code true} if so;
* otherwise it returns {@code false}. If this {@code Class}
* object represents a primitive type, this method returns
* {@code true} if the specified {@code Class} parameter is
* exactly this {@code Class} object; otherwise it returns
* {@code false}.
*
*
Specifically, this method tests whether the type represented by the
* specified {@code Class} parameter can be converted to the type
* represented by this {@code Class} object via an identity conversion
* or via a widening reference conversion. See The Java Language
* Specification, sections 5.1.1 and 5.1.4 , for details.
*
* @param cls the {@code Class} object to be checked
* @return the {@code boolean} value indicating whether objects of the
* type {@code cls} can be assigned to objects of this class
* @exception NullPointerException if the specified Class parameter is
* null.
* @since JDK1.1
*/
public native boolean isAssignableFrom(Class cls);
/**
* Determines if the specified {@code Class} object represents an
* interface type.
*
* @return {@code true} if this object represents an interface;
* {@code false} otherwise.
*/
public native boolean isInterface();
/**
* Determines if this {@code Class} object represents an array class.
*
* @return {@code true} if this object represents an array class;
* {@code false} otherwise.
* @since JDK1.1
*/
public native boolean isArray();
/**
* Determines if the specified {@code Class} object represents a
* primitive type.
*
*
There are nine predefined {@code Class} objects to represent
* the eight primitive types and void. These are created by the Java
* Virtual Machine, and have the same names as the primitive types that
* they represent, namely {@code boolean}, {@code byte},
* {@code char}, {@code short}, {@code int},
* {@code long}, {@code float}, and {@code double}.
*
*
These objects may only be accessed via the following public static
* final variables, and are the only {@code Class} objects for which
* this method returns {@code true}.
*
* @return true if and only if this class represents a primitive type
*
* @see java.lang.Boolean#TYPE
* @see java.lang.Character#TYPE
* @see java.lang.Byte#TYPE
* @see java.lang.Short#TYPE
* @see java.lang.Integer#TYPE
* @see java.lang.Long#TYPE
* @see java.lang.Float#TYPE
* @see java.lang.Double#TYPE
* @see java.lang.Void#TYPE
* @since JDK1.1
*/
public native boolean isPrimitive();
/**
* Returns true if this {@code Class} object represents an annotation
* type. Note that if this method returns true, {@link #isInterface()}
* would also return true, as all annotation types are also interfaces.
*
* @return {@code true} if this class object represents an annotation
* type; {@code false} otherwise
* @since 1.5
*/
public boolean isAnnotation() {
return (getModifiers() & ANNOTATION) != 0;
}
/**
* Returns {@code true} if this class is a synthetic class;
* returns {@code false} otherwise.
* @return {@code true} if and only if this class is a synthetic class as
* defined by the Java Language Specification.
* @since 1.5
*/
public boolean isSynthetic() {
return (getModifiers() & SYNTHETIC) != 0;
}
/**
* Returns the name of the entity (class, interface, array class,
* primitive type, or void) represented by this {@code Class} object,
* as a {@code String}.
*
*
If this class object represents a reference type that is not an
* array type then the binary name of the class is returned, as specified
* by
* The Java™ Language Specification.
*
*
If this class object represents a primitive type or void, then the
* name returned is a {@code String} equal to the Java language
* keyword corresponding to the primitive type or void.
*
*
If this class object represents a class of arrays, then the internal
* form of the name consists of the name of the element type preceded by
* one or more '{@code [}' characters representing the depth of the array
* nesting. The encoding of element type names is as follows:
*
*
*Element Type Encoding
*boolean Z
*byte B
*char C
*class or interface
*Lclassname;
*double D
*float F
*int I
*long J
*short S
*
The class or interface name classname is the binary name of
* the class specified above.
*
*
Examples:
*
* String.class.getName()
* returns "java.lang.String"
* byte.class.getName()
* returns "byte"
* (new Object[3]).getClass().getName()
* returns "[Ljava.lang.Object;"
* (new int[3][4][5][6][7][8][9]).getClass().getName()
* returns "[[[[[[[I"
*
If a security manager is present, and the caller's class loader is
* not null and the caller's class loader is not the same as or an ancestor of
* the class loader for the class whose class loader is requested, then
* this method calls the security manager's {@code checkPermission}
* method with a {@code RuntimePermission("getClassLoader")}
* permission to ensure it's ok to access the class loader for the class.
*
*
If this object
If the superclass is a parameterized type, the {@code Type}
Packages have attributes for versions and specifications only if the
If this object represents a class, the return value is an array
If this object represents an interface, the array contains objects
If this object represents a class or interface that implements no
If this object represents a primitive type or void, the method
If a superinterface is a parameterized type, the
If this object represents a class, the return value is an
If this object represents an interface, the array contains
If this object represents a class or interface that
If this object represents a primitive type or void, the
If the underlying class is an array class, then its
The modifier encodings are defined in The Java Virtual Machine
The simple name of an array is the simple name of the
Specifically, if this {@code Class} object represents a class,
The implicit length field for array class is not reflected by this
See The Java Language Specification, sections 8.2 and 8.3.
The class initialization method {@code See The Java Language Specification, sections 8.2 and 8.4.
The field to be reflected is determined by the algorithm that
See The Java Language Specification, sections 8.2 and 8.3.
If the {@code name} is "{@code Note that there may be more than one matching method in a
See The Java Language Specification, sections 8.2 and 8.4.
The constructor to reflect is the public constructor of the class
See The Java Language Specification, sections 8.2 and 8.3.
See The Java Language Specification, section 8.2.
See The Java Language Specification, section 8.2.
Before delegation, an absolute resource name is constructed from the
Where the {@code modified_package_name} is the package name of this
Before delegation, an absolute resource name is constructed from the
Where the {@code modified_package_name} is the package name of this
Default policy: allow all clients access with normal Java access
This method is useful when a client needs to "narrow" the type of
* represents a primitive type or void, null is returned.
*
* @return the class loader that loaded the class or interface
* represented by this object.
* @throws SecurityException
* if a security manager exists and its
* {@code checkPermission} method denies
* access to the class loader for the class.
* @see java.lang.ClassLoader
* @see SecurityManager#checkPermission
* @see java.lang.RuntimePermission
*/
@CallerSensitive
public ClassLoader getClassLoader() {
ClassLoader cl = getClassLoader0();
if (cl == null)
return null;
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
}
return cl;
}
// Package-private to allow ClassLoader access
native ClassLoader getClassLoader0();
/**
* Returns an array of {@code TypeVariable} objects that represent the
* type variables declared by the generic declaration represented by this
* {@code GenericDeclaration} object, in declaration order. Returns an
* array of length 0 if the underlying generic declaration declares no type
* variables.
*
* @return an array of {@code TypeVariable} objects that represent
* the type variables declared by this generic declaration
* @throws java.lang.reflect.GenericSignatureFormatError if the generic
* signature of this generic declaration does not conform to
* the format specified in
* The Java™ Virtual Machine Specification
* @since 1.5
*/
public TypeVariable
if (getGenericSignature() != null)
return (TypeVariable
else
return (TypeVariable
}
/**
* Returns the {@code Class} representing the superclass of the entity
* (class, interface, primitive type or void) represented by this
* {@code Class}. If this {@code Class} represents either the
* {@code Object} class, an interface, a primitive type, or void, then
* null is returned. If this object represents an array class then the
* {@code Class} object representing the {@code Object} class is
* returned.
*
* @return the superclass of the class represented by this object.
*/
public native Class getSuperclass();
/**
* Returns the {@code Type} representing the direct superclass of
* the entity (class, interface, primitive type or void) represented by
* this {@code Class}.
*
*
* object returned must accurately reflect the actual type
* parameters used in the source code. The parameterized type
* representing the superclass is created if it had not been
* created before. See the declaration of {@link
* java.lang.reflect.ParameterizedType ParameterizedType} for the
* semantics of the creation process for parameterized types. If
* this {@code Class} represents either the {@code Object}
* class, an interface, a primitive type, or void, then null is
* returned. If this object represents an array class then the
* {@code Class} object representing the {@code Object} class is
* returned.
*
* @throws java.lang.reflect.GenericSignatureFormatError if the generic
* class signature does not conform to the format specified in
* The Java™ Virtual Machine Specification
* @throws TypeNotPresentException if the generic superclass
* refers to a non-existent type declaration
* @throws java.lang.reflect.MalformedParameterizedTypeException if the
* generic superclass refers to a parameterized type that cannot be
* instantiated for any reason
* @return the superclass of the class represented by this object
* @since 1.5
*/
public Type getGenericSuperclass() {
if (getGenericSignature() != null) {
// Historical irregularity:
// Generic signature marks interfaces with superclass = Object
// but this API returns null for interfaces
if (isInterface())
return null;
return getGenericInfo().getSuperclass();
} else
return getSuperclass();
}
/**
* Gets the package for this class. The class loader of this class is used
* to find the package. If the class was loaded by the bootstrap class
* loader the set of packages loaded from CLASSPATH is searched to find the
* package of the class. Null is returned if no package object was created
* by the class loader of this class.
*
*
* information was defined in the manifests that accompany the classes, and
* if the class loader created the package instance with the attributes
* from the manifest.
*
* @return the package of the class, or null if no package
* information is available from the archive or codebase.
*/
public Package getPackage() {
return Package.getPackage(this);
}
/**
* Determines the interfaces implemented by the class or interface
* represented by this object.
*
*
* containing objects representing all interfaces implemented by the
* class. The order of the interface objects in the array corresponds to
* the order of the interface names in the {@code implements} clause
* of the declaration of the class represented by this object. For
* example, given the declaration:
*
* {@code class Shimmer implements FloorWax, DessertTopping { ... }}
*
* suppose the value of {@code s} is an instance of
* {@code Shimmer}; the value of the expression:
*
* {@code s.getClass().getInterfaces()[0]}
*
* is the {@code Class} object that represents interface
* {@code FloorWax}; and the value of:
*
* {@code s.getClass().getInterfaces()[1]}
*
* is the {@code Class} object that represents interface
* {@code DessertTopping}.
*
*
* representing all interfaces extended by the interface. The order of the
* interface objects in the array corresponds to the order of the interface
* names in the {@code extends} clause of the declaration of the
* interface represented by this object.
*
*
* interfaces, the method returns an array of length 0.
*
*
* returns an array of length 0.
*
* @return an array of interfaces implemented by this class.
*/
public native Class[] getInterfaces();
/**
* Returns the {@code Type}s representing the interfaces
* directly implemented by the class or interface represented by
* this object.
*
*
* {@code Type} object returned for it must accurately reflect
* the actual type parameters used in the source code. The
* parameterized type representing each superinterface is created
* if it had not been created before. See the declaration of
* {@link java.lang.reflect.ParameterizedType ParameterizedType}
* for the semantics of the creation process for parameterized
* types.
*
*
* array containing objects representing all interfaces
* implemented by the class. The order of the interface objects in
* the array corresponds to the order of the interface names in
* the {@code implements} clause of the declaration of the class
* represented by this object. In the case of an array class, the
* interfaces {@code Cloneable} and {@code Serializable} are
* returned in that order.
*
*
* objects representing all interfaces directly extended by the
* interface. The order of the interface objects in the array
* corresponds to the order of the interface names in the
* {@code extends} clause of the declaration of the interface
* represented by this object.
*
*
* implements no interfaces, the method returns an array of length
* 0.
*
*
* method returns an array of length 0.
*
* @throws java.lang.reflect.GenericSignatureFormatError
* if the generic class signature does not conform to the format
* specified in
* The Java™ Virtual Machine Specification
* @throws TypeNotPresentException if any of the generic
* superinterfaces refers to a non-existent type declaration
* @throws java.lang.reflect.MalformedParameterizedTypeException
* if any of the generic superinterfaces refer to a parameterized
* type that cannot be instantiated for any reason
* @return an array of interfaces implemented by this class
* @since 1.5
*/
public Type[] getGenericInterfaces() {
if (getGenericSignature() != null)
return getGenericInfo().getSuperInterfaces();
else
return getInterfaces();
}
/**
* Returns the {@code Class} representing the component type of an
* array. If this class does not represent an array class this method
* returns null.
*
* @return the {@code Class} representing the component type of this
* class if this class is an array
* @see java.lang.reflect.Array
* @since JDK1.1
*/
public native Class getComponentType();
/**
* Returns the Java language modifiers for this class or interface, encoded
* in an integer. The modifiers consist of the Java Virtual Machine's
* constants for {@code public}, {@code protected},
* {@code private}, {@code final}, {@code static},
* {@code abstract} and {@code interface}; they should be decoded
* using the methods of class {@code Modifier}.
*
*
* {@code public}, {@code private} and {@code protected}
* modifiers are the same as those of its component type. If this
* {@code Class} represents a primitive type or void, its
* {@code public} modifier is always {@code true}, and its
* {@code protected} and {@code private} modifiers are always
* {@code false}. If this object represents an array class, a
* primitive type or void, then its {@code final} modifier is always
* {@code true} and its interface modifier is always
* {@code false}. The values of its other modifiers are not determined
* by this specification.
*
*
* Specification, table 4.1.
*
* @return the {@code int} representing the modifiers for this class
* @see java.lang.reflect.Modifier
* @since JDK1.1
*/
public native int getModifiers();
/**
* Gets the signers of this class.
*
* @return the signers of this class, or null if there are no signers. In
* particular, this method returns null if this object represents
* a primitive type or void.
* @since JDK1.1
*/
public native Object[] getSigners();
/**
* Set the signers of this class.
*/
native void setSigners(Object[] signers);
/**
* If this {@code Class} object represents a local or anonymous
* class within a method, returns a {@link
* java.lang.reflect.Method Method} object representing the
* immediately enclosing method of the underlying class. Returns
* {@code null} otherwise.
*
* In particular, this method returns {@code null} if the underlying
* class is a local or anonymous class immediately enclosed by a type
* declaration, instance initializer or static initializer.
*
* @return the immediately enclosing method of the underlying class, if
* that class is a local or anonymous class; otherwise {@code null}.
* @since 1.5
*/
@CallerSensitive
public Method getEnclosingMethod() {
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
if (enclosingInfo == null)
return null;
else {
if (!enclosingInfo.isMethod())
return null;
MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
getFactory());
Class returnType = toClass(typeInfo.getReturnType());
Type [] parameterTypes = typeInfo.getParameterTypes();
Class[] parameterClasses = new Class[parameterTypes.length];
// Convert Types to Classes; returned types *should*
// be class objects since the methodDescriptor's used
// don't have generics information
for(int i = 0; i < parameterClasses.length; i++)
parameterClasses[i] = toClass(parameterTypes[i]);
// Perform access check
Class enclosingCandidate = enclosingInfo.getEnclosingClass();
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
//
// Note that we need to do this on the enclosing class
enclosingCandidate.checkMemberAccess(Member.DECLARED,
Reflection.getCallerClass(), true);
/*
* Loop over all declared methods; match method name,
* number of and type of parameters, *and* return
* type. Matching return type is also necessary
* because of covariant returns, etc.
*/
for(Method m: enclosingCandidate.getDeclaredMethods()) {
if (m.getName().equals(enclosingInfo.getName()) ) {
Class[] candidateParamClasses = m.getParameterTypes();
if (candidateParamClasses.length == parameterClasses.length) {
boolean matches = true;
for(int i = 0; i < candidateParamClasses.length; i++) {
if (!candidateParamClasses[i].equals(parameterClasses[i])) {
matches = false;
break;
}
}
if (matches) { // finally, check return type
if (m.getReturnType().equals(returnType) )
return m;
}
}
}
}
throw new InternalError("Enclosing method not found");
}
}
private native Object[] getEnclosingMethod0();
private EnclosingMethodInfo getEnclosingMethodInfo() {
Object[] enclosingInfo = getEnclosingMethod0();
if (enclosingInfo == null)
return null;
else {
return new EnclosingMethodInfo(enclosingInfo);
}
}
private final static class EnclosingMethodInfo {
private Class enclosingClass;
private String name;
private String descriptor;
private EnclosingMethodInfo(Object[] enclosingInfo) {
if (enclosingInfo.length != 3)
throw new InternalError("Malformed enclosing method information");
try {
// The array is expected to have three elements:
// the immediately enclosing class
enclosingClass = (Class) enclosingInfo[0];
assert(enclosingClass != null);
// the immediately enclosing method or constructor's
// name (can be null).
name = (String) enclosingInfo[1];
// the immediately enclosing method or constructor's
// descriptor (null iff name is).
descriptor = (String) enclosingInfo[2];
assert((name != null && descriptor != null) || name == descriptor);
} catch (ClassCastException cce) {
throw new InternalError("Invalid type in enclosing method information");
}
}
boolean isPartial() {
return enclosingClass == null || name == null || descriptor == null;
}
boolean isConstructor() { return !isPartial() && "
boolean isMethod() { return !isPartial() && !isConstructor() && !"
Class getEnclosingClass() { return enclosingClass; }
String getName() { return name; }
String getDescriptor() { return descriptor; }
}
private static Class toClass(Type o) {
if (o instanceof GenericArrayType)
return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
0)
.getClass();
return (Class)o;
}
/**
* If this {@code Class} object represents a local or anonymous
* class within a constructor, returns a {@link
* java.lang.reflect.Constructor Constructor} object representing
* the immediately enclosing constructor of the underlying
* class. Returns {@code null} otherwise. In particular, this
* method returns {@code null} if the underlying class is a local
* or anonymous class immediately enclosed by a type declaration,
* instance initializer or static initializer.
*
* @return the immediately enclosing constructor of the underlying class, if
* that class is a local or anonymous class; otherwise {@code null}.
* @since 1.5
*/
@CallerSensitive
public Constructor getEnclosingConstructor() {
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
if (enclosingInfo == null)
return null;
else {
if (!enclosingInfo.isConstructor())
return null;
ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
getFactory());
Type [] parameterTypes = typeInfo.getParameterTypes();
Class[] parameterClasses = new Class[parameterTypes.length];
// Convert Types to Classes; returned types *should*
// be class objects since the methodDescriptor's used
// don't have generics information
for(int i = 0; i < parameterClasses.length; i++)
parameterClasses[i] = toClass(parameterTypes[i]);
// Perform access check
Class enclosingCandidate = enclosingInfo.getEnclosingClass();
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
//
// Note that we need to do this on the enclosing class
enclosingCandidate.checkMemberAccess(Member.DECLARED,
Reflection.getCallerClass(), true);
/*
* Loop over all declared constructors; match number
* of and type of parameters.
*/
for(Constructor c: enclosingCandidate.getDeclaredConstructors()) {
Class[] candidateParamClasses = c.getParameterTypes();
if (candidateParamClasses.length == parameterClasses.length) {
boolean matches = true;
for(int i = 0; i < candidateParamClasses.length; i++) {
if (!candidateParamClasses[i].equals(parameterClasses[i])) {
matches = false;
break;
}
}
if (matches)
return c;
}
}
throw new InternalError("Enclosing constructor not found");
}
}
/**
* If the class or interface represented by this {@code Class} object
* is a member of another class, returns the {@code Class} object
* representing the class in which it was declared. This method returns
* null if this class or interface is not a member of any other class. If
* this {@code Class} object represents an array class, a primitive
* type, or void,then this method returns null.
*
* @return the declaring class for this class
* @since JDK1.1
*/
@CallerSensitive
public Class getDeclaringClass() {
final Class candidate = getDeclaringClass0();
if (candidate != null)
candidate.checkPackageAccess(
ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
return candidate;
}
private native Class getDeclaringClass0();
/**
* Returns the immediately enclosing class of the underlying
* class. If the underlying class is a top level class this
* method returns {@code null}.
* @return the immediately enclosing class of the underlying class
* @since 1.5
*/
@CallerSensitive
public Class getEnclosingClass() {
// There are five kinds of classes (or interfaces):
// a) Top level classes
// b) Nested classes (static member classes)
// c) Inner classes (non-static member classes)
// d) Local classes (named classes declared within a method)
// e) Anonymous classes
// JVM Spec 4.8.6: A class must have an EnclosingMethod
// attribute if and only if it is a local class or an
// anonymous class.
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
Class enclosingCandidate;
if (enclosingInfo == null) {
// This is a top level or a nested class or an inner class (a, b, or c)
enclosingCandidate = getDeclaringClass();
} else {
Class enclosingClass = enclosingInfo.getEnclosingClass();
// This is a local class or an anonymous class (d or e)
if (enclosingClass == this || enclosingClass == null)
throw new InternalError("Malformed enclosing method information");
else
enclosingCandidate = enclosingClass;
}
if (enclosingCandidate != null)
enclosingCandidate.checkPackageAccess(
ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
return enclosingCandidate;
}
/**
* Returns the simple name of the underlying class as given in the
* source code. Returns an empty string if the underlying class is
* anonymous.
*
*
* component type with "[]" appended. In particular the simple
* name of an array whose component type is anonymous is "[]".
*
* @return the simple name of the underlying class
* @since 1.5
*/
public String getSimpleName() {
if (isArray())
return getComponentType().getSimpleName()+"[]";
String simpleName = getSimpleBinaryName();
if (simpleName == null) { // top level class
simpleName = getName();
return simpleName.substring(simpleName.lastIndexOf(".")+1); // strip the package name
}
// According to JLS3 "Binary Compatibility" (13.1) the binary
// name of non-package classes (not top level) is the binary
// name of the immediately enclosing class followed by a '$' followed by:
// (for nested and inner classes): the simple name.
// (for local classes): 1 or more digits followed by the simple name.
// (for anonymous classes): 1 or more digits.
// Since getSimpleBinaryName() will strip the binary name of
// the immediatly enclosing class, we are now looking at a
// string that matches the regular expression "\$[0-9]*"
// followed by a simple name (considering the simple of an
// anonymous class to be the empty string).
// Remove leading "\$[0-9]*" from the name
int length = simpleName.length();
if (length < 1 || simpleName.charAt(0) != '$')
throw new InternalError("Malformed class name");
int index = 1;
while (index < length && isAsciiDigit(simpleName.charAt(index)))
index++;
// Eventually, this is the empty string iff this is an anonymous class
return simpleName.substring(index);
}
/**
* Character.isDigit answers {@code true} to some non-ascii
* digits. This one does not.
*/
private static boolean isAsciiDigit(char c) {
return '0' <= c && c <= '9';
}
/**
* Returns the canonical name of the underlying class as
* defined by the Java Language Specification. Returns null if
* the underlying class does not have a canonical name (i.e., if
* it is a local or anonymous class or an array whose component
* type does not have a canonical name).
* @return the canonical name of the underlying class if it exists, and
* {@code null} otherwise.
* @since 1.5
*/
public String getCanonicalName() {
if (isArray()) {
String canonicalName = getComponentType().getCanonicalName();
if (canonicalName != null)
return canonicalName + "[]";
else
return null;
}
if (isLocalOrAnonymousClass())
return null;
Class enclosingClass = getEnclosingClass();
if (enclosingClass == null) { // top level class
return getName();
} else {
String enclosingName = enclosingClass.getCanonicalName();
if (enclosingName == null)
return null;
return enclosingName + "." + getSimpleName();
}
}
/**
* Returns {@code true} if and only if the underlying class
* is an anonymous class.
*
* @return {@code true} if and only if this class is an anonymous class.
* @since 1.5
*/
public boolean isAnonymousClass() {
return "".equals(getSimpleName());
}
/**
* Returns {@code true} if and only if the underlying class
* is a local class.
*
* @return {@code true} if and only if this class is a local class.
* @since 1.5
*/
public boolean isLocalClass() {
return isLocalOrAnonymousClass() && !isAnonymousClass();
}
/**
* Returns {@code true} if and only if the underlying class
* is a member class.
*
* @return {@code true} if and only if this class is a member class.
* @since 1.5
*/
public boolean isMemberClass() {
return getSimpleBinaryName() != null && !isLocalOrAnonymousClass();
}
/**
* Returns the "simple binary name" of the underlying class, i.e.,
* the binary name without the leading enclosing class name.
* Returns {@code null} if the underlying class is a top level
* class.
*/
private String getSimpleBinaryName() {
Class enclosingClass = getEnclosingClass();
if (enclosingClass == null) // top level class
return null;
// Otherwise, strip the enclosing class' name
try {
return getName().substring(enclosingClass.getName().length());
} catch (IndexOutOfBoundsException ex) {
throw new InternalError("Malformed class name");
}
}
/**
* Returns {@code true} if this is a local class or an anonymous
* class. Returns {@code false} otherwise.
*/
private boolean isLocalOrAnonymousClass() {
// JVM Spec 4.8.6: A class must have an EnclosingMethod
// attribute if and only if it is a local class or an
// anonymous class.
return getEnclosingMethodInfo() != null;
}
/**
* Returns an array containing {@code Class} objects representing all
* the public classes and interfaces that are members of the class
* represented by this {@code Class} object. This includes public
* class and interface members inherited from superclasses and public class
* and interface members declared by the class. This method returns an
* array of length 0 if this {@code Class} object has no public member
* classes or interfaces. This method also returns an array of length 0 if
* this {@code Class} object represents a primitive type, an array
* class, or void.
*
* @return the array of {@code Class} objects representing the public
* members of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} method
* denies access to the classes within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Class[] getClasses() {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
// Privileged so this implementation can look at DECLARED classes,
// something the caller might not have privilege to do. The code here
// is allowed to look at DECLARED classes because (1) it does not hand
// out anything other than public members and (2) public member access
// has already been ok'd by the SecurityManager.
return java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction
public Class[] run() {
List
Class currentClass = Class.this;
while (currentClass != null) {
Class[] members = currentClass.getDeclaredClasses();
for (int i = 0; i < members.length; i++) {
if (Modifier.isPublic(members[i].getModifiers())) {
list.add(members[i]);
}
}
currentClass = currentClass.getSuperclass();
}
return list.toArray(new Class[0]);
}
});
}
/**
* Returns an array containing {@code Field} objects reflecting all
* the accessible public fields of the class or interface represented by
* this {@code Class} object. The elements in the array returned are
* not sorted and are not in any particular order. This method returns an
* array of length 0 if the class or interface has no accessible public
* fields, or if it represents an array class, a primitive type, or void.
*
*
* this method returns the public fields of this class and of all its
* superclasses. If this {@code Class} object represents an
* interface, this method returns the fields of this interface and of all
* its superinterfaces.
*
*
* method. User code should use the methods of class {@code Array} to
* manipulate arrays.
*
*
*
* @return the array of {@code Field} objects representing the
* public fields
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the fields within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Field[] getFields() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return copyFields(privateGetPublicFields(null));
}
/**
* Returns an array containing {@code Method} objects reflecting all
* the public member methods of the class or interface represented
* by this {@code Class} object, including those declared by the class
* or interface and those inherited from superclasses and
* superinterfaces. Array classes return all the (public) member methods
* inherited from the {@code Object} class. The elements in the array
* returned are not sorted and are not in any particular order. This
* method returns an array of length 0 if this {@code Class} object
* represents a class or interface that has no public member methods, or if
* this {@code Class} object represents a primitive type or void.
*
*
* included in the returned array. If the class declares multiple public
* member methods with the same parameter types, they are all included in
* the returned array.
*
*
*
* @return the array of {@code Method} objects representing the
* public methods of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the methods within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Method[] getMethods() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return copyMethods(privateGetPublicMethods());
}
/**
* Returns an array containing {@code Constructor} objects reflecting
* all the public constructors of the class represented by this
* {@code Class} object. An array of length 0 is returned if the
* class has no public constructors, or if the class is an array class, or
* if the class reflects a primitive type or void.
*
* Note that while this method returns an array of {@code
* Constructor
* this class), the return type of this method is {@code
* Constructor[]} and not {@code Constructor
* might be expected. This less informative return type is
* necessary since after being returned from this method, the
* array could be modified to hold {@code Constructor} objects for
* different classes, which would violate the type guarantees of
* {@code Constructor
*
* @return the array of {@code Constructor} objects representing the
* public constructors of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the constructors within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Constructor[] getConstructors() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return copyConstructors(privateGetDeclaredConstructors(true));
}
/**
* Returns a {@code Field} object that reflects the specified public
* member field of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} specifying the simple name of the desired field.
*
*
* follows. Let C be the class represented by this object:
*
*
* field to be reflected.
*
* recursively to each direct superinterface of C. The direct
* superinterfaces are searched in the order they were declared.
*
* superclass S, then this algorithm is invoked recursively upon S.
* If C has no superclass, then a {@code NoSuchFieldException}
* is thrown.
*
*
*
*
* @param name the field name
* @return the {@code Field} object of this class specified by
* {@code name}
* @exception NoSuchFieldException if a field with the specified name is
* not found.
* @exception NullPointerException if {@code name} is {@code null}
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the field
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Field getField(String name)
throws NoSuchFieldException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
Field field = getField0(name);
if (field == null) {
throw new NoSuchFieldException(name);
}
return field;
}
/**
* Returns a {@code Method} object that reflects the specified public
* member method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} specifying the simple name of the desired method. The
* {@code parameterTypes} parameter is an array of {@code Class}
* objects that identify the method's formal parameter types, in declared
* order. If {@code parameterTypes} is {@code null}, it is
* treated as if it were an empty array.
*
*
* {@code NoSuchMethodException} is raised. Otherwise, the method to
* be reflected is determined by the algorithm that follows. Let C be the
* class represented by this object:
*
*
* method is found, the algorithm of step 1 is invoked recursively on
* the superclass of C.
*
* are searched for a matching method. If any such method is found, it
* is reflected.
*
*
* To find a matching method in a class C: If C declares exactly one
* public method with the specified name and exactly the same formal
* parameter types, that is the method reflected. If more than one such
* method is found in C, and one of these methods has a return type that is
* more specific than any of the others, that method is reflected;
* otherwise one of the methods is chosen arbitrarily.
*
*
* class because while the Java language forbids a class to
* declare multiple methods with the same signature but different
* return types, the Java virtual machine does not. This
* increased flexibility in the virtual machine can be used to
* implement various language features. For example, covariant
* returns can be implemented with {@linkplain
* java.lang.reflect.Method#isBridge bridge methods}; the bridge
* method and the method being overridden would have the same
* signature but different return types.
*
*
*
* @param name the name of the method
* @param parameterTypes the list of parameters
* @return the {@code Method} object that matches the specified
* {@code name} and {@code parameterTypes}
* @exception NoSuchMethodException if a matching method is not found
* or if the name is "<init>"or "<clinit>".
* @exception NullPointerException if {@code name} is {@code null}
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the method
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Method getMethod(String name, Class... parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
Method method = getMethod0(name, parameterTypes);
if (method == null) {
throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
}
return method;
}
/**
* Returns a {@code Constructor} object that reflects the specified
* public constructor of the class represented by this {@code Class}
* object. The {@code parameterTypes} parameter is an array of
* {@code Class} objects that identify the constructor's formal
* parameter types, in declared order.
*
* If this {@code Class} object represents an inner class
* declared in a non-static context, the formal parameter types
* include the explicit enclosing instance as the first parameter.
*
*
* represented by this {@code Class} object whose formal parameter
* types match those specified by {@code parameterTypes}.
*
* @param parameterTypes the parameter array
* @return the {@code Constructor} object of the public constructor that
* matches the specified {@code parameterTypes}
* @exception NoSuchMethodException if a matching method is not found.
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the constructor
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Constructor
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return getConstructor0(parameterTypes, Member.PUBLIC);
}
/**
* Returns an array of {@code Class} objects reflecting all the
* classes and interfaces declared as members of the class represented by
* this {@code Class} object. This includes public, protected, default
* (package) access, and private classes and interfaces declared by the
* class, but excludes inherited classes and interfaces. This method
* returns an array of length 0 if the class declares no classes or
* interfaces as members, or if this {@code Class} object represents a
* primitive type, an array class, or void.
*
* @return the array of {@code Class} objects representing all the
* declared members of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared classes within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Class[] getDeclaredClasses() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), false);
return getDeclaredClasses0();
}
/**
* Returns an array of {@code Field} objects reflecting all the fields
* declared by the class or interface represented by this
* {@code Class} object. This includes public, protected, default
* (package) access, and private fields, but excludes inherited fields.
* The elements in the array returned are not sorted and are not in any
* particular order. This method returns an array of length 0 if the class
* or interface declares no fields, or if this {@code Class} object
* represents a primitive type, an array class, or void.
*
*
*
* @return the array of {@code Field} objects representing all the
* declared fields of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared fields within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Field[] getDeclaredFields() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyFields(privateGetDeclaredFields(false));
}
/**
* Returns an array of {@code Method} objects reflecting all the
* methods declared by the class or interface represented by this
* {@code Class} object. This includes public, protected, default
* (package) access, and private methods, but excludes inherited methods.
* The elements in the array returned are not sorted and are not in any
* particular order. This method returns an array of length 0 if the class
* or interface declares no methods, or if this {@code Class} object
* represents a primitive type, an array class, or void. The class
* initialization method {@code
* returned array. If the class declares multiple public member methods
* with the same parameter types, they are all included in the returned
* array.
*
*
*
* @return the array of {@code Method} objects representing all the
* declared methods of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared methods within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Method[] getDeclaredMethods() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyMethods(privateGetDeclaredMethods(false));
}
/**
* Returns an array of {@code Constructor} objects reflecting all the
* constructors declared by the class represented by this
* {@code Class} object. These are public, protected, default
* (package) access, and private constructors. The elements in the array
* returned are not sorted and are not in any particular order. If the
* class has a default constructor, it is included in the returned array.
* This method returns an array of length 0 if this {@code Class}
* object represents an interface, a primitive type, an array class, or
* void.
*
*
*
* @return the array of {@code Constructor} objects representing all the
* declared constructors of this class
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared constructors within this class
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Constructor[] getDeclaredConstructors() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyConstructors(privateGetDeclaredConstructors(false));
}
/**
* Returns a {@code Field} object that reflects the specified declared
* field of the class or interface represented by this {@code Class}
* object. The {@code name} parameter is a {@code String} that
* specifies the simple name of the desired field. Note that this method
* will not reflect the {@code length} field of an array class.
*
* @param name the name of the field
* @return the {@code Field} object for the specified field in this
* class
* @exception NoSuchFieldException if a field with the specified name is
* not found.
* @exception NullPointerException if {@code name} is {@code null}
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared field
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Field getDeclaredField(String name)
throws NoSuchFieldException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
Field field = searchFields(privateGetDeclaredFields(false), name);
if (field == null) {
throw new NoSuchFieldException(name);
}
return field;
}
/**
* Returns a {@code Method} object that reflects the specified
* declared method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} that specifies the simple name of the desired
* method, and the {@code parameterTypes} parameter is an array of
* {@code Class} objects that identify the method's formal parameter
* types, in declared order. If more than one method with the same
* parameter types is declared in a class, and one of these methods has a
* return type that is more specific than any of the others, that method is
* returned; otherwise one of the methods is chosen arbitrarily. If the
* name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
* is raised.
*
* @param name the name of the method
* @param parameterTypes the parameter array
* @return the {@code Method} object for the method of this class
* matching the specified name and parameters
* @exception NoSuchMethodException if a matching method is not found.
* @exception NullPointerException if {@code name} is {@code null}
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared method
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Method getDeclaredMethod(String name, Class... parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
if (method == null) {
throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
}
return method;
}
/**
* Returns a {@code Constructor} object that reflects the specified
* constructor of the class or interface represented by this
* {@code Class} object. The {@code parameterTypes} parameter is
* an array of {@code Class} objects that identify the constructor's
* formal parameter types, in declared order.
*
* If this {@code Class} object represents an inner class
* declared in a non-static context, the formal parameter types
* include the explicit enclosing instance as the first parameter.
*
* @param parameterTypes the parameter array
* @return The {@code Constructor} object for the constructor with the
* specified parameter list
* @exception NoSuchMethodException if a matching method is not found.
* @exception SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.DECLARED)} denies
* access to the declared constructor
*
*
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
*
*
* @since JDK1.1
*/
@CallerSensitive
public Constructor
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return getConstructor0(parameterTypes, Member.DECLARED);
}
/**
* Finds a resource with a given name. The rules for searching resources
* associated with a given class are implemented by the defining
* {@linkplain ClassLoader class loader} of the class. This method
* delegates to this object's class loader. If this object was loaded by
* the bootstrap class loader, the method delegates to {@link
* ClassLoader#getSystemResourceAsStream}.
*
*
* given resource name using this algorithm:
*
*
*
*
* ('\u002f'), then the absolute name of the resource is the
* portion of the {@code name} following the {@code '/'}.
*
*
*
*
* {@code modified_package_name/name}
*
*
*
* object with {@code '/'} substituted for {@code '.'}
* ('\u002e').
*
*
*
* @param name name of the desired resource
* @return A {@link java.io.InputStream} object or {@code null} if
* no resource with this name is found
* @throws NullPointerException If {@code name} is {@code null}
* @since JDK1.1
*/
public InputStream getResourceAsStream(String name) {
name = resolveName(name);
ClassLoader cl = getClassLoader0();
if (cl==null) {
// A system class.
return ClassLoader.getSystemResourceAsStream(name);
}
return cl.getResourceAsStream(name);
}
/**
* Finds a resource with a given name. The rules for searching resources
* associated with a given class are implemented by the defining
* {@linkplain ClassLoader class loader} of the class. This method
* delegates to this object's class loader. If this object was loaded by
* the bootstrap class loader, the method delegates to {@link
* ClassLoader#getSystemResource}.
*
*
* given resource name using this algorithm:
*
*
*
*
* ('\u002f'), then the absolute name of the resource is the
* portion of the {@code name} following the {@code '/'}.
*
*
*
*
* {@code modified_package_name/name}
*
*
*
* object with {@code '/'} substituted for {@code '.'}
* ('\u002e').
*
*
*
* @param name name of the desired resource
* @return A {@link java.net.URL} object or {@code null} if no
* resource with this name is found
* @since JDK1.1
*/
public java.net.URL getResource(String name) {
name = resolveName(name);
ClassLoader cl = getClassLoader0();
if (cl==null) {
// A system class.
return ClassLoader.getSystemResource(name);
}
return cl.getResource(name);
}
/** protection domain returned when the internal domain is null */
private static java.security.ProtectionDomain allPermDomain;
/**
* Returns the {@code ProtectionDomain} of this class. If there is a
* security manager installed, this method first calls the security
* manager's {@code checkPermission} method with a
* {@code RuntimePermission("getProtectionDomain")} permission to
* ensure it's ok to get the
* {@code ProtectionDomain}.
*
* @return the ProtectionDomain of this class
*
* @throws SecurityException
* if a security manager exists and its
* {@code checkPermission} method doesn't allow
* getting the ProtectionDomain.
*
* @see java.security.ProtectionDomain
* @see SecurityManager#checkPermission
* @see java.lang.RuntimePermission
* @since 1.2
*/
public java.security.ProtectionDomain getProtectionDomain() {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
}
java.security.ProtectionDomain pd = getProtectionDomain0();
if (pd == null) {
if (allPermDomain == null) {
java.security.Permissions perms =
new java.security.Permissions();
perms.add(SecurityConstants.ALL_PERMISSION);
allPermDomain =
new java.security.ProtectionDomain(null, perms);
}
pd = allPermDomain;
}
return pd;
}
/**
* Returns the ProtectionDomain of this class.
*/
private native java.security.ProtectionDomain getProtectionDomain0();
/**
* Set the ProtectionDomain for this class. Called by
* ClassLoader.defineClass.
*/
native void setProtectionDomain0(java.security.ProtectionDomain pd);
/*
* Return the Virtual Machine's Class object for the named
* primitive type.
*/
static native Class getPrimitiveClass(String name);
private static class SecurityManagerHelper {
final SecurityManager sm;
final boolean overrideCheckMemberAccess;
SecurityManagerHelper(SecurityManager sm) {
this.sm = sm;
boolean overridden = false;
if (sm.getClass() != SecurityManager.class) {
try {
overridden = getCheckMemberAccessMethod(sm.getClass()).
getDeclaringClass() != SecurityManager.class;
} catch (NoSuchMethodError e) {
// fall back to invoke sm.checkMemberAccess for the member access check
}
}
this.overrideCheckMemberAccess = overridden;
}
}
private static volatile SecurityManagerHelper smHelper;
private static boolean isCheckMemberAccessOverridden(SecurityManager sm) {
if (sm.getClass() == SecurityManager.class) return false;
SecurityManagerHelper helper = smHelper;
if (helper == null || helper.sm != sm) {
helper = new SecurityManagerHelper(sm);
smHelper = helper;
}
return helper.overrideCheckMemberAccess;
}
/**
* Finds the checkMemberAccess method of the given SecurityManager class.
*
* This method calls JNI_GetMethodID to look up the checkMemberAccess method
* instead of Class.getMethod0 that may cause loading of classes referenced
* by the SecurityManager subclass and cause ClassCircularityError.
*
* JNI_GetMethodID may throw NoSuchMethodError if the given class
* has a static checkMemberAccess method.
*
* @throws NoSuchMethodError if the method cannot be found.
*/
private static native Method getCheckMemberAccessMethod(Class c)
throws NoSuchMethodError;
/*
* Check if client is allowed to access members. If access is denied,
* throw a SecurityException.
*
* This method also enforces package access.
*
*
* control.
*/
private void checkMemberAccess(int which, Class caller, boolean checkProxyInterfaces) {
final SecurityManager s = System.getSecurityManager();
if (s != null) {
final ClassLoader ccl = ClassLoader.getClassLoader(caller);
final ClassLoader cl = getClassLoader0();
if (!isCheckMemberAccessOverridden(s)) {
// Inlined SecurityManager.checkMemberAccess
if (which != Member.PUBLIC) {
if (ccl != cl) {
s.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
}
}
} else {
// Don't refactor; otherwise break the stack depth for
// checkMemberAccess of subclasses of SecurityManager as specified.
s.checkMemberAccess(this, which);
}
this.checkPackageAccess(ccl, checkProxyInterfaces);
}
}
/*
* Checks if a client loaded in ClassLoader ccl is allowed to access this
* class under the current package access policy. If access is denied,
* throw a SecurityException.
*/
private void checkPackageAccess(final ClassLoader ccl, boolean checkProxyInterfaces) {
final SecurityManager s = System.getSecurityManager();
if (s != null) {
final ClassLoader cl = getClassLoader0();
if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
String name = this.getName();
int i = name.lastIndexOf('.');
if (i != -1) {
// skip the package access check on a proxy class in default proxy package
String pkg = name.substring(0, i);
if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
s.checkPackageAccess(pkg);
}
}
}
// check package access on the proxy interfaces
if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
}
}
}
/**
* Add a package name prefix if the name is not absolute Remove leading "/"
* if name is absolute
*/
private String resolveName(String name) {
if (name == null) {
return name;
}
if (!name.startsWith("/")) {
Class c = this;
while (c.isArray()) {
c = c.getComponentType();
}
String baseName = c.getName();
int index = baseName.lastIndexOf('.');
if (index != -1) {
name = baseName.substring(0, index).replace('.', '/')
+"/"+name;
}
} else {
name = name.substring(1);
}
return name;
}
/**
* Atomic operations support.
*/
private static class Atomic {
// initialize Unsafe machinery here, since we need to call Class.class instance method
// and have to avoid calling it in the static initializer of the Class class...
private static final Unsafe unsafe = Unsafe.getUnsafe();
// offset of Class.reflectionData instance field
private static final long reflectionDataOffset;
// offset of Class.annotationType instance field
private static final long annotationTypeOffset;
static {
Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches
reflectionDataOffset = objectFieldOffset(fields, "reflectionData");
annotationTypeOffset = objectFieldOffset(fields, "annotationType");
}
private static long objectFieldOffset(Field[] fields, String fieldName) {
Field field = searchFields(fields, fieldName);
if (field == null) {
throw new Error("No " + fieldName + " field found in java.lang.Class");
}
return unsafe.objectFieldOffset(field);
}
static
SoftReference
SoftReference
return unsafe.compareAndSwapObject(clazz, reflectionDataOffset, oldData, newData);
}
static
AnnotationType oldType,
AnnotationType newType) {
return unsafe.compareAndSwapObject(clazz, annotationTypeOffset, oldType, newType);
}
}
/**
* Reflection support.
*/
// Caches for certain reflective results
private static boolean useCaches = true;
// reflection data that might get invalidated when JVM TI RedefineClasses() is called
static class ReflectionData
volatile Field[] declaredFields;
volatile Field[] publicFields;
volatile Method[] declaredMethods;
volatile Method[] publicMethods;
volatile Constructor
volatile Constructor
// Intermediate results for getFields and getMethods
volatile Field[] declaredPublicFields;
volatile Method[] declaredPublicMethods;
// Value of classRedefinedCount when we created this ReflectionData instance
final int redefinedCount;
ReflectionData(int redefinedCount) {
this.redefinedCount = redefinedCount;
}
}
private volatile transient SoftReference
// Incremented by the VM on each call to JVM TI RedefineClasses()
// that redefines this class or a superclass.
private volatile transient int classRedefinedCount = 0;
// Lazily create and cache ReflectionData
private ReflectionData
SoftReference
int classRedefinedCount = this.classRedefinedCount;
ReflectionData
if (useCaches &&
reflectionData != null &&
(rd = reflectionData.get()) != null &&
rd.redefinedCount == classRedefinedCount) {
return rd;
}
// else no SoftReference or cleared SoftReference or stale ReflectionData
// -> create and replace new instance
return newReflectionData(reflectionData, classRedefinedCount);
}
private ReflectionData
int classRedefinedCount) {
if (!useCaches) return null;
while (true) {
ReflectionData
// try to CAS it...
if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
return rd;
}
// else retry
oldReflectionData = this.reflectionData;
classRedefinedCount = this.classRedefinedCount;
if (oldReflectionData != null &&
(rd = oldReflectionData.get()) != null &&
rd.redefinedCount == classRedefinedCount) {
return rd;
}
}
}
// Generic signature handling
private native String getGenericSignature();
// Generic info repository; lazily initialized
private transient ClassRepository genericInfo;
// accessor for factory
private GenericsFactory getFactory() {
// create scope and factory
return CoreReflectionFactory.make(this, ClassScope.make(this));
}
// accessor for generic info repository
private ClassRepository getGenericInfo() {
// lazily initialize repository if necessary
if (genericInfo == null) {
// create and cache generic info repository
genericInfo = ClassRepository.make(getGenericSignature(),
getFactory());
}
return genericInfo; //return cached repository
}
// Annotations handling
native byte[] getRawAnnotations();
native ConstantPool getConstantPool();
//
//
// java.lang.reflect.Field handling
//
//
// Returns an array of "root" fields. These Field objects must NOT
// be propagated to the outside world, but must instead be copied
// via ReflectionFactory.copyField.
private Field[] privateGetDeclaredFields(boolean publicOnly) {
checkInitted();
Field[] res;
ReflectionData
if (rd != null) {
res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
if (res != null) return res;
}
// No cached value available; request value from VM
res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
if (rd != null) {
if (publicOnly) {
rd.declaredPublicFields = res;
} else {
rd.declaredFields = res;
}
}
return res;
}
// Returns an array of "root" fields. These Field objects must NOT
// be propagated to the outside world, but must instead be copied
// via ReflectionFactory.copyField.
private Field[] privateGetPublicFields(Set
checkInitted();
Field[] res;
ReflectionData
if (rd != null) {
res = rd.publicFields;
if (res != null) return res;
}
// No cached value available; compute value recursively.
// Traverse in correct order for getField().
List
if (traversedInterfaces == null) {
traversedInterfaces = new HashSet<>();
}
// Local fields
Field[] tmp = privateGetDeclaredFields(true);
addAll(fields, tmp);
// Direct superinterfaces, recursively
for (Class c : getInterfaces()) {
if (!traversedInterfaces.contains(c)) {
traversedInterfaces.add(c);
addAll(fields, c.privateGetPublicFields(traversedInterfaces));
}
}
// Direct superclass, recursively
if (!isInterface()) {
Class c = getSuperclass();
if (c != null) {
addAll(fields, c.privateGetPublicFields(traversedInterfaces));
}
}
res = new Field[fields.size()];
fields.toArray(res);
if (rd != null) {
rd.publicFields = res;
}
return res;
}
private static void addAll(Collection
for (int i = 0; i < o.length; i++) {
c.add(o[i]);
}
}
//
//
// java.lang.reflect.Constructor handling
//
//
// Returns an array of "root" constructors. These Constructor
// objects must NOT be propagated to the outside world, but must
// instead be copied via ReflectionFactory.copyConstructor.
private Constructor
checkInitted();
Constructor
ReflectionData
if (rd != null) {
res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
if (res != null) return res;
}
// No cached value available; request value from VM
if (isInterface()) {
res = new Constructor[0];
} else {
res = getDeclaredConstructors0(publicOnly);
}
if (rd != null) {
if (publicOnly) {
rd.publicConstructors = res;
} else {
rd.declaredConstructors = res;
}
}
return res;
}
//
//
// java.lang.reflect.Method handling
//
//
// Returns an array of "root" methods. These Method objects must NOT
// be propagated to the outside world, but must instead be copied
// via ReflectionFactory.copyMethod.
private Method[] privateGetDeclaredMethods(boolean publicOnly) {
checkInitted();
Method[] res;
ReflectionData
if (rd != null) {
res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
if (res != null) return res;
}
// No cached value available; request value from VM
res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
if (rd != null) {
if (publicOnly) {
rd.declaredPublicMethods = res;
} else {
rd.declaredMethods = res;
}
}
return res;
}
static class MethodArray {
private Method[] methods;
private int length;
MethodArray() {
methods = new Method[20];
length = 0;
}
void add(Method m) {
if (length == methods.length) {
methods = Arrays.copyOf(methods, 2 * methods.length);
}
methods[length++] = m;
}
void addAll(Method[] ma) {
for (int i = 0; i < ma.length; i++) {
add(ma[i]);
}
}
void addAll(MethodArray ma) {
for (int i = 0; i < ma.length(); i++) {
add(ma.get(i));
}
}
void addIfNotPresent(Method newMethod) {
for (int i = 0; i < length; i++) {
Method m = methods[i];
if (m == newMethod || (m != null && m.equals(newMethod))) {
return;
}
}
add(newMethod);
}
void addAllIfNotPresent(MethodArray newMethods) {
for (int i = 0; i < newMethods.length(); i++) {
Method m = newMethods.get(i);
if (m != null) {
addIfNotPresent(m);
}
}
}
int length() {
return length;
}
Method get(int i) {
return methods[i];
}
void removeByNameAndSignature(Method toRemove) {
for (int i = 0; i < length; i++) {
Method m = methods[i];
if (m != null &&
m.getReturnType() == toRemove.getReturnType() &&
m.getName() == toRemove.getName() &&
arrayContentsEq(m.getParameterTypes(),
toRemove.getParameterTypes())) {
methods[i] = null;
}
}
}
void compactAndTrim() {
int newPos = 0;
// Get rid of null slots
for (int pos = 0; pos < length; pos++) {
Method m = methods[pos];
if (m != null) {
if (pos != newPos) {
methods[newPos] = m;
}
newPos++;
}
}
if (newPos != methods.length) {
methods = Arrays.copyOf(methods, newPos);
}
}
Method[] getArray() {
return methods;
}
}
// Returns an array of "root" methods. These Method objects must NOT
// be propagated to the outside world, but must instead be copied
// via ReflectionFactory.copyMethod.
private Method[] privateGetPublicMethods() {
checkInitted();
Method[] res;
ReflectionData
if (rd != null) {
res = rd.publicMethods;
if (res != null) return res;
}
// No cached value available; compute value recursively.
// Start by fetching public declared methods
MethodArray methods = new MethodArray();
{
Method[] tmp = privateGetDeclaredMethods(true);
methods.addAll(tmp);
}
// Now recur over superclass and direct superinterfaces.
// Go over superinterfaces first so we can more easily filter
// out concrete implementations inherited from superclasses at
// the end.
MethodArray inheritedMethods = new MethodArray();
Class[] interfaces = getInterfaces();
for (int i = 0; i < interfaces.length; i++) {
inheritedMethods.addAll(interfaces[i].privateGetPublicMethods());
}
if (!isInterface()) {
Class c = getSuperclass();
if (c != null) {
MethodArray supers = new MethodArray();
supers.addAll(c.privateGetPublicMethods());
// Filter out concrete implementations of any
// interface methods
for (int i = 0; i < supers.length(); i++) {
Method m = supers.get(i);
if (m != null && !Modifier.isAbstract(m.getModifiers())) {
inheritedMethods.removeByNameAndSignature(m);
}
}
// Insert superclass's inherited methods before
// superinterfaces' to satisfy getMethod's search
// order
supers.addAll(inheritedMethods);
inheritedMethods = supers;
}
}
// Filter out all local methods from inherited ones
for (int i = 0; i < methods.length(); i++) {
Method m = methods.get(i);
inheritedMethods.removeByNameAndSignature(m);
}
methods.addAllIfNotPresent(inheritedMethods);
methods.compactAndTrim();
res = methods.getArray();
if (rd != null) {
rd.publicMethods = res;
}
return res;
}
//
// Helpers for fetchers of one field, method, or constructor
//
private static Field searchFields(Field[] fields, String name) {
String internedName = name.intern();
for (int i = 0; i < fields.length; i++) {
if (fields[i].getName() == internedName) {
return getReflectionFactory().copyField(fields[i]);
}
}
return null;
}
private Field getField0(String name) throws NoSuchFieldException {
// Note: the intent is that the search algorithm this routine
// uses be equivalent to the ordering imposed by
// privateGetPublicFields(). It fetches only the declared
// public fields for each class, however, to reduce the number
// of Field objects which have to be created for the common
// case where the field being requested is declared in the
// class which is being queried.
Field res;
// Search declared public fields
if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
return res;
}
// Direct superinterfaces, recursively
Class[] interfaces = getInterfaces();
for (int i = 0; i < interfaces.length; i++) {
Class c = interfaces[i];
if ((res = c.getField0(name)) != null) {
return res;
}
}
// Direct superclass, recursively
if (!isInterface()) {
Class c = getSuperclass();
if (c != null) {
if ((res = c.getField0(name)) != null) {
return res;
}
}
}
return null;
}
private static Method searchMethods(Method[] methods,
String name,
Class[] parameterTypes)
{
Method res = null;
String internedName = name.intern();
for (int i = 0; i < methods.length; i++) {
Method m = methods[i];
if (m.getName() == internedName
&& arrayContentsEq(parameterTypes, m.getParameterTypes())
&& (res == null
|| res.getReturnType().isAssignableFrom(m.getReturnType())))
res = m;
}
return (res == null ? res : getReflectionFactory().copyMethod(res));
}
private Method getMethod0(String name, Class[] parameterTypes) {
// Note: the intent is that the search algorithm this routine
// uses be equivalent to the ordering imposed by
// privateGetPublicMethods(). It fetches only the declared
// public methods for each class, however, to reduce the
// number of Method objects which have to be created for the
// common case where the method being requested is declared in
// the class which is being queried.
Method res;
// Search declared public methods
if ((res = searchMethods(privateGetDeclaredMethods(true),
name,
parameterTypes)) != null) {
return res;
}
// Search superclass's methods
if (!isInterface()) {
Class c = getSuperclass();
if (c != null) {
if ((res = c.getMethod0(name, parameterTypes)) != null) {
return res;
}
}
}
// Search superinterfaces' methods
Class[] interfaces = getInterfaces();
for (int i = 0; i < interfaces.length; i++) {
Class c = interfaces[i];
if ((res = c.getMethod0(name, parameterTypes)) != null) {
return res;
}
}
// Not found
return null;
}
private Constructor
int which) throws NoSuchMethodException
{
Constructor
for (Constructor
if (arrayContentsEq(parameterTypes,
constructor.getParameterTypes())) {
return getReflectionFactory().copyConstructor(constructor);
}
}
throw new NoSuchMethodException(getName() + ".
}
//
// Other helpers and base implementation
//
private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
if (a1 == null) {
return a2 == null || a2.length == 0;
}
if (a2 == null) {
return a1.length == 0;
}
if (a1.length != a2.length) {
return false;
}
for (int i = 0; i < a1.length; i++) {
if (a1[i] != a2[i]) {
return false;
}
}
return true;
}
private static Field[] copyFields(Field[] arg) {
Field[] out = new Field[arg.length];
ReflectionFactory fact = getReflectionFactory();
for (int i = 0; i < arg.length; i++) {
out[i] = fact.copyField(arg[i]);
}
return out;
}
private static Method[] copyMethods(Method[] arg) {
Method[] out = new Method[arg.length];
ReflectionFactory fact = getReflectionFactory();
for (int i = 0; i < arg.length; i++) {
out[i] = fact.copyMethod(arg[i]);
}
return out;
}
private static Constructor[] copyConstructors(Constructor[] arg) {
Constructor[] out = arg.clone();
ReflectionFactory fact = getReflectionFactory();
for (int i = 0; i < out.length; i++) {
out[i] = fact.copyConstructor(out[i]);
}
return out;
}
private native Field[] getDeclaredFields0(boolean publicOnly);
private native Method[] getDeclaredMethods0(boolean publicOnly);
private native Constructor
private native Class[] getDeclaredClasses0();
private static String argumentTypesToString(Class[] argTypes) {
StringBuilder buf = new StringBuilder();
buf.append("(");
if (argTypes != null) {
for (int i = 0; i < argTypes.length; i++) {
if (i > 0) {
buf.append(", ");
}
Class c = argTypes[i];
buf.append((c == null) ? "null" : c.getName());
}
}
buf.append(")");
return buf.toString();
}
/** use serialVersionUID from JDK 1.1 for interoperability */
private static final long serialVersionUID = 3206093459760846163L;
/**
* Class Class is special cased within the Serialization Stream Protocol.
*
* A Class instance is written initially into an ObjectOutputStream in the
* following format:
*
* {@code TC_CLASS} ClassDescriptor
* A ClassDescriptor is a special cased serialization of
* a {@code java.io.ObjectStreamClass} instance.
*
* A new handle is generated for the initial time the class descriptor
* is written into the stream. Future references to the class descriptor
* are written as references to the initial class descriptor instance.
*
* @see java.io.ObjectStreamClass
*/
private static final ObjectStreamField[] serialPersistentFields =
new ObjectStreamField[0];
/**
* Returns the assertion status that would be assigned to this
* class if it were to be initialized at the time this method is invoked.
* If this class has had its assertion status set, the most recent
* setting will be returned; otherwise, if any package default assertion
* status pertains to this class, the most recent setting for the most
* specific pertinent package default assertion status is returned;
* otherwise, if this class is not a system class (i.e., it has a
* class loader) its class loader's default assertion status is returned;
* otherwise, the system class default assertion status is returned.
*
* Few programmers will have any need for this method; it is provided
* for the benefit of the JRE itself. (It allows a class to determine at
* the time that it is initialized whether assertions should be enabled.)
* Note that this method is not guaranteed to return the actual
* assertion status that was (or will be) associated with the specified
* class when it was (or will be) initialized.
*
* @return the desired assertion status of the specified class.
* @see java.lang.ClassLoader#setClassAssertionStatus
* @see java.lang.ClassLoader#setPackageAssertionStatus
* @see java.lang.ClassLoader#setDefaultAssertionStatus
* @since 1.4
*/
public boolean desiredAssertionStatus() {
ClassLoader loader = getClassLoader();
// If the loader is null this is a system class, so ask the VM
if (loader == null)
return desiredAssertionStatus0(this);
// If the classloader has been initialized with the assertion
// directives, ask it. Otherwise, ask the VM.
synchronized(loader.assertionLock) {
if (loader.classAssertionStatus != null) {
return loader.desiredAssertionStatus(getName());
}
}
return desiredAssertionStatus0(this);
}
// Retrieves the desired assertion status of this class from the VM
private static native boolean desiredAssertionStatus0(Class clazz);
/**
* Returns true if and only if this class was declared as an enum in the
* source code.
*
* @return true if and only if this class was declared as an enum in the
* source code
* @since 1.5
*/
public boolean isEnum() {
// An enum must both directly extend java.lang.Enum and have
// the ENUM bit set; classes for specialized enum constants
// don't do the former.
return (this.getModifiers() & ENUM) != 0 &&
this.getSuperclass() == java.lang.Enum.class;
}
// Fetches the factory for reflective objects
private static ReflectionFactory getReflectionFactory() {
if (reflectionFactory == null) {
reflectionFactory =
java.security.AccessController.doPrivileged
(new sun.reflect.ReflectionFactory.GetReflectionFactoryAction());
}
return reflectionFactory;
}
private static ReflectionFactory reflectionFactory;
// To be able to query system properties as soon as they're available
private static boolean initted = false;
private static void checkInitted() {
if (initted) return;
AccessController.doPrivileged(new PrivilegedAction
public Void run() {
// Tests to ensure the system properties table is fully
// initialized. This is needed because reflection code is
// called very early in the initialization process (before
// command-line arguments have been parsed and therefore
// these user-settable properties installed.) We assume that
// if System.out is non-null then the System class has been
// fully initialized and that the bulk of the startup code
// has been run.
if (System.out == null) {
// java.lang.System not yet fully initialized
return null;
}
String val =
System.getProperty("sun.reflect.noCaches");
if (val != null && val.equals("true")) {
useCaches = false;
}
initted = true;
return null;
}
});
}
/**
* Returns the elements of this enum class or null if this
* Class object does not represent an enum type.
*
* @return an array containing the values comprising the enum class
* represented by this Class object in the order they're
* declared, or null if this Class object does not
* represent an enum type
* @since 1.5
*/
public T[] getEnumConstants() {
T[] values = getEnumConstantsShared();
return (values != null) ? values.clone() : null;
}
/**
* Returns the elements of this enum class or null if this
* Class object does not represent an enum type;
* identical to getEnumConstants except that the result is
* uncloned, cached, and shared by all callers.
*/
T[] getEnumConstantsShared() {
if (enumConstants == null) {
if (!isEnum()) return null;
try {
final Method values = getMethod("values");
java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction
public Void run() {
values.setAccessible(true);
return null;
}
});
enumConstants = (T[])values.invoke(null);
}
// These can happen when users concoct enum-like classes
// that don't comply with the enum spec.
catch (InvocationTargetException ex) { return null; }
catch (NoSuchMethodException ex) { return null; }
catch (IllegalAccessException ex) { return null; }
}
return enumConstants;
}
private volatile transient T[] enumConstants = null;
/**
* Returns a map from simple name to enum constant. This package-private
* method is used internally by Enum to implement
* public static
* efficiently. Note that the map is returned by this method is
* created lazily on first use. Typically it won't ever get created.
*/
Map
if (enumConstantDirectory == null) {
T[] universe = getEnumConstantsShared();
if (universe == null)
throw new IllegalArgumentException(
getName() + " is not an enum type");
Map
for (T constant : universe)
m.put(((Enum)constant).name(), constant);
enumConstantDirectory = m;
}
return enumConstantDirectory;
}
private volatile transient Map
/**
* Casts an object to the class or interface represented
* by this {@code Class} object.
*
* @param obj the object to be cast
* @return the object after casting, or null if obj is null
*
* @throws ClassCastException if the object is not
* null and is not assignable to the type T.
*
* @since 1.5
*/
public T cast(Object obj) {
if (obj != null && !isInstance(obj))
throw new ClassCastException(cannotCastMsg(obj));
return (T) obj;
}
private String cannotCastMsg(Object obj) {
return "Cannot cast " + obj.getClass().getName() + " to " + getName();
}
/**
* Casts this {@code Class} object to represent a subclass of the class
* represented by the specified class object. Checks that that the cast
* is valid, and throws a {@code ClassCastException} if it is not. If
* this method succeeds, it always returns a reference to this class object.
*
*
* a {@code Class} object to pass it to an API that restricts the
* {@code Class} objects that it is willing to accept. A cast would
* generate a compile-time warning, as the correctness of the cast
* could not be checked at runtime (because generic types are implemented
* by erasure).
*
* @return this {@code Class} object, cast to represent a subclass of
* the specified class object.
* @throws ClassCastException if this {@code Class} object does not
* represent a subclass of the specified class (here "subclass" includes
* the class itself).
* @since 1.5
*/
public Class asSubclass(Class clazz) {
if (clazz.isAssignableFrom(this))
return (Class) this;
else
throw new ClassCastException(this.toString());
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.5
*/
public A getAnnotation(Class annotationClass) {
if (annotationClass == null)
throw new NullPointerException();
initAnnotationsIfNecessary();
return (A) annotations.get(annotationClass);
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.5
*/
public boolean isAnnotationPresent(
Class annotationClass) {
if (annotationClass == null)
throw new NullPointerException();
return getAnnotation(annotationClass) != null;
}
/**
* @since 1.5
*/
public Annotation[] getAnnotations() {
initAnnotationsIfNecessary();
return AnnotationParser.toArray(annotations);
}
/**
* @since 1.5
*/
public Annotation[] getDeclaredAnnotations() {
initAnnotationsIfNecessary();
return AnnotationParser.toArray(declaredAnnotations);
}
// Annotations cache
private transient Map
private transient Map
// Value of classRedefinedCount when we last cleared the cached annotations and declaredAnnotations fields
private transient int lastAnnotationsRedefinedCount = 0;
// Clears cached values that might possibly have been obsoleted by
// a class redefinition.
private void clearAnnotationCachesOnClassRedefinition() {
if (lastAnnotationsRedefinedCount != classRedefinedCount) {
annotations = declaredAnnotations = null;
lastAnnotationsRedefinedCount = classRedefinedCount;
}
}
private synchronized void initAnnotationsIfNecessary() {
clearAnnotationCachesOnClassRedefinition();
if (annotations != null)
return;
declaredAnnotations = AnnotationParser.parseAnnotations(
getRawAnnotations(), getConstantPool(), this);
Class superClass = getSuperclass();
if (superClass == null) {
annotations = declaredAnnotations;
} else {
annotations = new HashMap<>();
superClass.initAnnotationsIfNecessary();
for (Map.Entry
Class annotationClass = e.getKey();
if (AnnotationType.getInstance(annotationClass).isInherited())
annotations.put(annotationClass, e.getValue());
}
annotations.putAll(declaredAnnotations);
}
}
// Annotation types cache their internal (AnnotationType) form
@SuppressWarnings("UnusedDeclaration")
private volatile transient AnnotationType annotationType;
boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
return Atomic.casAnnotationType(this, oldType, newType);
}
AnnotationType getAnnotationType() {
return annotationType;
}
/* Backing store of user-defined values pertaining to this class.
* Maintained by the ClassValue class.
*/
transient ClassValue.ClassValueMap classValueMap;
}