java反射工具

package org.liufei.jweb.reflection;

import java.lang.reflect.Field;
import java.util.Map;

import org.liufei.jweb.util.Assert;
import org.liufei.jweb.util.ClassUtils;

/**
 * Bean注入(通过字段注入)工具。
 * 
 * @author 刘飞
 * 
 */
public class BeanFieldInjector {

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标类字符串。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanByField(String target,
			Map<String, Object> parameters) throws ClassNotFoundException,
			LinkageError, InstantiationException, IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Class<?> targetClass = ClassUtils.forName(target, BeanFieldInjector.class
				.getClassLoader());

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			ReflectionUtils.makeAccessible(field);
			if(parameters.containsKey(field.getName()))
				ReflectionUtils.setField(field, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName())));
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标类。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanByField(Class<?> target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Class<?> targetClass = target;

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			ReflectionUtils.makeAccessible(field);
			if(parameters.containsKey(field.getName()))
				ReflectionUtils.setField(field, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName())));
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标对象。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanByField(Object target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Object object = target;

		Class<?> targetClass = object.getClass();

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			ReflectionUtils.makeAccessible(field);
			if(parameters.containsKey(field.getName()))
				ReflectionUtils.setField(field, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName())));
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到字段target对应的类型实例化对象中并返回。
	 * 
	 * @param target
	 *            目标字段。
	 * @param parameters
	 *            参数集合, 以target字段名称为键和它对应的类型中的字段名称为键。
	 *            
	 *            如:User user = new User() ;通过user.name注入。
	 *            
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setFieldBeanByField(Field target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {

		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		String fieldName = target.getName();

		Class<?> targetClass = target.getType();

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			ReflectionUtils.makeAccessible(field);
			if(parameters.containsKey(fieldName + "." + field.getName()))
				ReflectionUtils.setField(field, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(fieldName + "." + field.getName())));
		}
		return targetBean;

	}
}
package org.liufei.jweb.reflection;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Map;

import org.liufei.jweb.util.Assert;
import org.liufei.jweb.util.ClassUtils;

/**
 * Bean注入工具(setter方法注入)。
 * 
 * @author 刘飞
 * 
 */
public class BeanMethodInjector {

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标类字符串。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanBySetMethod(String target,
			Map<String, Object> parameters) throws ClassNotFoundException,
			LinkageError, InstantiationException, IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Class<?> targetClass = ClassUtils.forName(target, BeanMethodInjector.class
				.getClassLoader());

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			Method setMethod = getSetMethodByField(targetClass, field) ;
			if(parameters.containsKey(field.getName()) && setMethod != null)
				ReflectionUtils.invokeMethod(setMethod, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName()))) ;
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标类。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanBySetMethod(Class<?> target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Class<?> targetClass = target;

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			Method setMethod = getSetMethodByField(targetClass, field) ;
			if(parameters.containsKey(field.getName()) && setMethod != null)
				ReflectionUtils.invokeMethod(setMethod, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName()))) ;
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到target实例化对象中并返回。
	 * 
	 * @param target
	 *            目标对象。
	 * @param parameters
	 *            参数集合, 以字段名称为键。
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setBeanBySetMethod(Object target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {
		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		Object object = target;

		Class<?> targetClass = object.getClass();

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			Method setMethod = getSetMethodByField(targetClass, field) ;
			if(parameters.containsKey(field.getName()) && setMethod != null)
				ReflectionUtils.invokeMethod(setMethod, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(field.getName()))) ;
		}
		return targetBean;
	}

	/**
	 * 将指定参数[Map : parameters]注入到字段target对应的类型实例化对象中并返回。
	 * 
	 * @param target
	 *            目标字段。
	 * @param parameters
	 *            参数集合, 以target字段名称为键和它对应的类型中的字段名称为键。
	 *            
	 *            如:User user = new User() ;通过user.name注入。
	 *            
	 * @return 返回注入的实例结果。
	 * @throws ClassNotFoundException
	 * @throws LinkageError
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 */
	public Object setFieldBeanBySetMethod(Field target,
			Map<String, Object> parameters) throws InstantiationException,
			IllegalAccessException {

		Assert.notNull(target, "target class must not be null");
		Assert.notEmpty(parameters, "parameters map must not be null");

		String fieldName = target.getName();

		Class<?> targetClass = target.getType();

		Object targetBean = targetClass.newInstance();

		Field[] allFields = ReflectionUtils.getAllDeclaredFields(targetClass);

		for (Field field : allFields) {
			Method setMethod = this.getSetMethodByField(targetClass, field) ;
			if(parameters.containsKey(fieldName + "." + field.getName()) && setMethod != null)
				ReflectionUtils.invokeMethod(setMethod, targetBean, ReflectionUtils.simpleTypeValue(field.getType(), parameters.get(fieldName + "." + field.getName()))) ;
		}
		return targetBean;

	}
	
	private Method getSetMethodByField(Class<?> clazz, Field field) {
		String fieldName = field.getName() ;
		String setMethodName = "set" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1, fieldName.length()) ;
		return ReflectionUtils.findMethod(clazz, setMethodName, field.getType()) ;
	}
}
package org.liufei.jweb.reflection;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.sql.Date;
import java.sql.SQLException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.liufei.jweb.util.ArrayUtils;
import org.liufei.jweb.util.Assert;

public abstract class ReflectionUtils {

	/**
	 * Attempt to find a {@link Field field} on the supplied {@link Class} with the
	 * supplied <code>name</code>. Searches all superclasses up to {@link Object}.
	 * @param clazz the class to introspect
	 * @param name the name of the field
	 * @return the corresponding Field object, or <code>null</code> if not found
	 */
	public static Field findField(Class<?> clazz, String name) {
		return findField(clazz, name, null);
	}

	/**
	 * Attempt to find a {@link Field field} on the supplied {@link Class} with the
	 * supplied <code>name</code> and/or {@link Class type}. Searches all superclasses
	 * up to {@link Object}.
	 * @param clazz the class to introspect
	 * @param name the name of the field (may be <code>null</code> if type is specified)
	 * @param type the type of the field (may be <code>null</code> if name is specified)
	 * @return the corresponding Field object, or <code>null</code> if not found
	 */
	public static Field findField(Class<?> clazz, String name, Class<?> type) {
		Assert.notNull(clazz, "Class must not be null");
		Assert.isTrue(name != null || type != null, "Either name or type of the field must be specified");
		Class<?> searchType = clazz;
		while (!Object.class.equals(searchType) && searchType != null) {
			Field[] fields = searchType.getDeclaredFields();
			for (Field field : fields) {
				if ((name == null || name.equals(field.getName())) && (type == null || type.equals(field.getType()))) {
					return field;
				}
			}
			searchType = searchType.getSuperclass();
		}
		return null;
	}
	
	/**
	 * 获取本类以及父类的所有字段。
	 * 
	 * @param leafClass
	 * @return
	 */
	public static Field[] getAllDeclaredFields(Class<?> leafClass) {
		Assert.notNull(leafClass, "Class must not be null");
		Class<?> searchType = leafClass ;
		Class<?> superType = searchType.getSuperclass() ;
		Field[] searchTypeFields = searchType.getDeclaredFields() ;
		Field[] superTypeFields = superType.getDeclaredFields() ;
		return (Field[]) ArrayUtils.addAll(searchTypeFields, superTypeFields);
	}

	/**
	 * Set the field represented by the supplied {@link Field field object} on the
	 * specified {@link Object target object} to the specified <code>value</code>.
	 * In accordance with {@link Field#set(Object, Object)} semantics, the new value
	 * is automatically unwrapped if the underlying field has a primitive type.
	 * <p>Thrown exceptions are handled via a call to {@link #handleReflectionException(Exception)}.
	 * @param field the field to set
	 * @param target the target object on which to set the field
	 * @param value the value to set; may be <code>null</code>
	 */
	public static void setField(Field field, Object target, Object value) {
		try {
			field.set(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException("Unexpected reflection exception - " + ex.getClass().getName() + ": "
					+ ex.getMessage());
		}
	}
	
	public static Object simpleTypeValue(Class<?> type, Object value) {
		Object result = value ;
		if(type == int.class || type == Integer.class) {
			result = Integer.parseInt(result.toString()) ;
		}
		else if(type == long.class || type == Long.class) {
			result = Long.parseLong(result.toString()) ;
		}
		else if(type == char.class || type == Character.class) {
			result = result.toString().charAt(0) ;
		}
		else if(type == float.class || type == Float.class) {
			result = Float.parseFloat(result.toString()) ;
		}
		else if(type == double.class || type == Double.class) {
			result = Double.parseDouble(result.toString()) ;
		}
		else if(type == byte.class || type == Byte.class) {
			result = Byte.parseByte(result.toString()) ;
		}
		else if(type == short.class || type == Short.class) {
			result = Short.parseShort(result.toString()) ;
		}
		else if(type == boolean.class || type == Boolean.class) {
			result = Boolean.parseBoolean(result.toString()) ;
		}
		else if(type == Date.class) {
			result = Date.valueOf(result.toString()) ;
		}
		else if(type == java.util.Date.class) {
			try {
				result = new SimpleDateFormat().parse(result.toString()) ;
			} catch (ParseException e) {
				result = value ;
			}
		}
		return result ;
	}
	
	public static void setField(Field field, Object target, int value) {
		try {
			field.setInt(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, long value) {
		try {
			field.setLong(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, boolean value) {
		try {
			field.setBoolean(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, byte value) {
		try {
			field.setByte(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, char value) {
		try {
			field.setChar(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, double value) {
		try {
			field.setDouble(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, float value) {
		try {
			field.setFloat(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}
	
	public static void setField(Field field, Object target, short value) {
		try {
			field.setShort(target, value);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}

	/**
	 * Get the field represented by the supplied {@link Field field object} on the
	 * specified {@link Object target object}. In accordance with {@link Field#get(Object)}
	 * semantics, the returned value is automatically wrapped if the underlying field
	 * has a primitive type.
	 * <p>Thrown exceptions are handled via a call to {@link #handleReflectionException(Exception)}.
	 * @param field the field to get
	 * @param target the target object from which to get the field
	 * @return the field's current value
	 */
	public static Object getField(Field field, Object target) {
		try {
			return field.get(target);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
			throw new IllegalStateException(
					"Unexpected reflection exception - " + ex.getClass().getName() + ": " + ex.getMessage());
		}
	}

	/**
	 * Attempt to find a {@link Method} on the supplied class with the supplied name
	 * and no parameters. Searches all superclasses up to <code>Object</code>.
	 * <p>Returns <code>null</code> if no {@link Method} can be found.
	 * @param clazz the class to introspect
	 * @param name the name of the method
	 * @return the Method object, or <code>null</code> if none found
	 */
	public static Method findMethod(Class<?> clazz, String name) {
		return findMethod(clazz, name, new Class[0]);
	}

	/**
	 * Attempt to find a {@link Method} on the supplied class with the supplied name
	 * and parameter types. Searches all superclasses up to <code>Object</code>.
	 * <p>Returns <code>null</code> if no {@link Method} can be found.
	 * @param clazz the class to introspect
	 * @param name the name of the method
	 * @param paramTypes the parameter types of the method
	 * (may be <code>null</code> to indicate any signature)
	 * @return the Method object, or <code>null</code> if none found
	 */
	public static Method findMethod(Class<?> clazz, String name, Class<?>... paramTypes) {
		Assert.notNull(clazz, "Class must not be null");
		Assert.notNull(name, "Method name must not be null");
		Class<?> searchType = clazz;
		while (searchType != null) {
			Method[] methods = (searchType.isInterface() ? searchType.getMethods() : searchType.getDeclaredMethods());
			for (Method method : methods) {
				if (name.equals(method.getName())
						&& (paramTypes == null || Arrays.equals(paramTypes, method.getParameterTypes()))) {
					return method;
				}
			}
			searchType = searchType.getSuperclass();
		}
		return null;
	}

	/**
	 * Invoke the specified {@link Method} against the supplied target object with no arguments.
	 * The target object can be <code>null</code> when invoking a static {@link Method}.
	 * <p>Thrown exceptions are handled via a call to {@link #handleReflectionException}.
	 * @param method the method to invoke
	 * @param target the target object to invoke the method on
	 * @return the invocation result, if any
	 * @see #invokeMethod(java.lang.reflect.Method, Object, Object[])
	 */
	public static Object invokeMethod(Method method, Object target) {
		return invokeMethod(method, target, new Object[0]);
	}

	/**
	 * Invoke the specified {@link Method} against the supplied target object with the
	 * supplied arguments. The target object can be <code>null</code> when invoking a
	 * static {@link Method}.
	 * <p>Thrown exceptions are handled via a call to {@link #handleReflectionException}.
	 * @param method the method to invoke
	 * @param target the target object to invoke the method on
	 * @param args the invocation arguments (may be <code>null</code>)
	 * @return the invocation result, if any
	 */
	public static Object invokeMethod(Method method, Object target, Object... args) {
		try {
			return method.invoke(target, args);
		}
		catch (Exception ex) {
			handleReflectionException(ex);
		}
		throw new IllegalStateException("Should never get here");
	}

	/**
	 * Invoke the specified JDBC API {@link Method} against the supplied target
	 * object with no arguments.
	 * @param method the method to invoke
	 * @param target the target object to invoke the method on
	 * @return the invocation result, if any
	 * @throws SQLException the JDBC API SQLException to rethrow (if any)
	 * @see #invokeJdbcMethod(java.lang.reflect.Method, Object, Object[])
	 */
	public static Object invokeJdbcMethod(Method method, Object target) throws SQLException {
		return invokeJdbcMethod(method, target, new Object[0]);
	}

	/**
	 * Invoke the specified JDBC API {@link Method} against the supplied target
	 * object with the supplied arguments.
	 * @param method the method to invoke
	 * @param target the target object to invoke the method on
	 * @param args the invocation arguments (may be <code>null</code>)
	 * @return the invocation result, if any
	 * @throws SQLException the JDBC API SQLException to rethrow (if any)
	 * @see #invokeMethod(java.lang.reflect.Method, Object, Object[])
	 */
	public static Object invokeJdbcMethod(Method method, Object target, Object... args) throws SQLException {
		try {
			return method.invoke(target, args);
		}
		catch (IllegalAccessException ex) {
			handleReflectionException(ex);
		}
		catch (InvocationTargetException ex) {
			if (ex.getTargetException() instanceof SQLException) {
				throw (SQLException) ex.getTargetException();
			}
			handleInvocationTargetException(ex);
		}
		throw new IllegalStateException("Should never get here");
	}

	/**
	 * Handle the given reflection exception. Should only be called if no
	 * checked exception is expected to be thrown by the target method.
	 * <p>Throws the underlying RuntimeException or Error in case of an
	 * InvocationTargetException with such a root cause. Throws an
	 * IllegalStateException with an appropriate message else.
	 * @param ex the reflection exception to handle
	 */
	public static void handleReflectionException(Exception ex) {
		if (ex instanceof NoSuchMethodException) {
			throw new IllegalStateException("Method not found: " + ex.getMessage());
		}
		if (ex instanceof IllegalAccessException) {
			throw new IllegalStateException("Could not access method: " + ex.getMessage());
		}
		if (ex instanceof InvocationTargetException) {
			handleInvocationTargetException((InvocationTargetException) ex);
		}
		if (ex instanceof RuntimeException) {
			throw (RuntimeException) ex;
		}
		handleUnexpectedException(ex);
	}

	/**
	 * Handle the given invocation target exception. Should only be called if no
	 * checked exception is expected to be thrown by the target method.
	 * <p>Throws the underlying RuntimeException or Error in case of such a root
	 * cause. Throws an IllegalStateException else.
	 * @param ex the invocation target exception to handle
	 */
	public static void handleInvocationTargetException(InvocationTargetException ex) {
		rethrowRuntimeException(ex.getTargetException());
	}

	/**
	 * Rethrow the given {@link Throwable exception}, which is presumably the
	 * <em>target exception</em> of an {@link InvocationTargetException}. Should
	 * only be called if no checked exception is expected to be thrown by the
	 * target method.
	 * <p>Rethrows the underlying exception cast to an {@link RuntimeException} or
	 * {@link Error} if appropriate; otherwise, throws an
	 * {@link IllegalStateException}.
	 * @param ex the exception to rethrow
	 * @throws RuntimeException the rethrown exception
	 */
	public static void rethrowRuntimeException(Throwable ex) {
		if (ex instanceof RuntimeException) {
			throw (RuntimeException) ex;
		}
		if (ex instanceof Error) {
			throw (Error) ex;
		}
		handleUnexpectedException(ex);
	}

	/**
	 * Rethrow the given {@link Throwable exception}, which is presumably the
	 * <em>target exception</em> of an {@link InvocationTargetException}. Should
	 * only be called if no checked exception is expected to be thrown by the
	 * target method.
	 * <p>Rethrows the underlying exception cast to an {@link Exception} or
	 * {@link Error} if appropriate; otherwise, throws an
	 * {@link IllegalStateException}.
	 * @param ex the exception to rethrow
	 * @throws Exception the rethrown exception (in case of a checked exception)
	 */
	public static void rethrowException(Throwable ex) throws Exception {
		if (ex instanceof Exception) {
			throw (Exception) ex;
		}
		if (ex instanceof Error) {
			throw (Error) ex;
		}
		handleUnexpectedException(ex);
	}

	/**
	 * Throws an IllegalStateException with the given exception as root cause.
	 * @param ex the unexpected exception
	 */
	private static void handleUnexpectedException(Throwable ex) {
		throw new IllegalStateException("Unexpected exception thrown", ex);
	}

	/**
	 * Determine whether the given method explicitly declares the given
	 * exception or one of its superclasses, which means that an exception of
	 * that type can be propagated as-is within a reflective invocation.
	 * @param method the declaring method
	 * @param exceptionType the exception to throw
	 * @return <code>true</code> if the exception can be thrown as-is;
	 * <code>false</code> if it needs to be wrapped
	 */
	public static boolean declaresException(Method method, Class<?> exceptionType) {
		Assert.notNull(method, "Method must not be null");
		Class<?>[] declaredExceptions = method.getExceptionTypes();
		for (Class<?> declaredException : declaredExceptions) {
			if (declaredException.isAssignableFrom(exceptionType)) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Determine whether the given field is a "public static final" constant.
	 * @param field the field to check
	 */
	public static boolean isPublicStaticFinal(Field field) {
		int modifiers = field.getModifiers();
		return (Modifier.isPublic(modifiers) && Modifier.isStatic(modifiers) && Modifier.isFinal(modifiers));
	}

	/**
	 * Determine whether the given method is an "equals" method.
	 * @see java.lang.Object#equals(Object)
	 */
	public static boolean isEqualsMethod(Method method) {
		if (method == null || !method.getName().equals("equals")) {
			return false;
		}
		Class<?>[] paramTypes = method.getParameterTypes();
		return (paramTypes.length == 1 && paramTypes[0] == Object.class);
	}

	/**
	 * Determine whether the given method is a "hashCode" method.
	 * @see java.lang.Object#hashCode()
	 */
	public static boolean isHashCodeMethod(Method method) {
		return (method != null && method.getName().equals("hashCode") && method.getParameterTypes().length == 0);
	}

	/**
	 * Determine whether the given method is a "toString" method.
	 * @see java.lang.Object#toString()
	 */
	public static boolean isToStringMethod(Method method) {
		return (method != null && method.getName().equals("toString") && method.getParameterTypes().length == 0);
	}

	/**
	 * Make the given field accessible, explicitly setting it accessible if
	 * necessary. The <code>setAccessible(true)</code> method is only called
	 * when actually necessary, to avoid unnecessary conflicts with a JVM
	 * SecurityManager (if active).
	 * @param field the field to make accessible
	 * @see java.lang.reflect.Field#setAccessible
	 */
	public static void makeAccessible(Field field) {
		if ((!Modifier.isPublic(field.getModifiers()) || !Modifier.isPublic(field.getDeclaringClass().getModifiers()) ||
				Modifier.isFinal(field.getModifiers())) && !field.isAccessible()) {
			field.setAccessible(true);
		}
	}

	/**
	 * Make the given method accessible, explicitly setting it accessible if
	 * necessary. The <code>setAccessible(true)</code> method is only called
	 * when actually necessary, to avoid unnecessary conflicts with a JVM
	 * SecurityManager (if active).
	 * @param method the method to make accessible
	 * @see java.lang.reflect.Method#setAccessible
	 */
	public static void makeAccessible(Method method) {
		if ((!Modifier.isPublic(method.getModifiers()) || !Modifier.isPublic(method.getDeclaringClass().getModifiers()))
				&& !method.isAccessible()) {
			method.setAccessible(true);
		}
	}

	/**
	 * Make the given constructor accessible, explicitly setting it accessible
	 * if necessary. The <code>setAccessible(true)</code> method is only called
	 * when actually necessary, to avoid unnecessary conflicts with a JVM
	 * SecurityManager (if active).
	 * @param ctor the constructor to make accessible
	 * @see java.lang.reflect.Constructor#setAccessible
	 */
	public static void makeAccessible(Constructor<?> ctor) {
		if ((!Modifier.isPublic(ctor.getModifiers()) || !Modifier.isPublic(ctor.getDeclaringClass().getModifiers()))
				&& !ctor.isAccessible()) {
			ctor.setAccessible(true);
		}
	}

	/**
	 * Perform the given callback operation on all matching methods of the given
	 * class and superclasses.
	 * <p>The same named method occurring on subclass and superclass will appear
	 * twice, unless excluded by a {@link MethodFilter}.
	 * @param clazz class to start looking at
	 * @param mc the callback to invoke for each method
	 * @see #doWithMethods(Class, MethodCallback, MethodFilter)
	 */
	public static void doWithMethods(Class<?> clazz, MethodCallback mc) throws IllegalArgumentException {
		doWithMethods(clazz, mc, null);
	}

	/**
	 * Perform the given callback operation on all matching methods of the given
	 * class and superclasses (or given interface and super-interfaces).
	 * <p>The same named method occurring on subclass and superclass will appear
	 * twice, unless excluded by the specified {@link MethodFilter}.
	 * @param clazz class to start looking at
	 * @param mc the callback to invoke for each method
	 * @param mf the filter that determines the methods to apply the callback to
	 */
	public static void doWithMethods(Class<?> clazz, MethodCallback mc, MethodFilter mf)
			throws IllegalArgumentException {

		// Keep backing up the inheritance hierarchy.
		Method[] methods = clazz.getDeclaredMethods();
		for (Method method : methods) {
			if (mf != null && !mf.matches(method)) {
				continue;
			}
			try {
				mc.doWith(method);
			}
			catch (IllegalAccessException ex) {
				throw new IllegalStateException("Shouldn't be illegal to access method '" + method.getName()
						+ "': " + ex);
			}
		}
		if (clazz.getSuperclass() != null) {
			doWithMethods(clazz.getSuperclass(), mc, mf);
		}
		else if (clazz.isInterface()) {
			for (Class<?> superIfc : clazz.getInterfaces()) {
				doWithMethods(superIfc, mc, mf);
			}
		}
	}

	/**
	 * Get all declared methods on the leaf class and all superclasses. Leaf
	 * class methods are included first.
	 */
	public static Method[] getAllDeclaredMethods(Class<?> leafClass) throws IllegalArgumentException {
		final List<Method> methods = new ArrayList<Method>(32);
		doWithMethods(leafClass, new MethodCallback() {
			public void doWith(Method method) {
				methods.add(method);
			}
		});
		return methods.toArray(new Method[methods.size()]);
	}

	/**
	 * Invoke the given callback on all fields in the target class, going up the
	 * class hierarchy to get all declared fields.
	 * @param clazz the target class to analyze
	 * @param fc the callback to invoke for each field
	 */
	public static void doWithFields(Class<?> clazz, FieldCallback fc) throws IllegalArgumentException {
		doWithFields(clazz, fc, null);
	}

	/**
	 * Invoke the given callback on all fields in the target class, going up the
	 * class hierarchy to get all declared fields.
	 * @param clazz the target class to analyze
	 * @param fc the callback to invoke for each field
	 * @param ff the filter that determines the fields to apply the callback to
	 */
	public static void doWithFields(Class<?> clazz, FieldCallback fc, FieldFilter ff)
			throws IllegalArgumentException {

		// Keep backing up the inheritance hierarchy.
		Class<?> targetClass = clazz;
		do {
			Field[] fields = targetClass.getDeclaredFields();
			for (Field field : fields) {
				// Skip static and final fields.
				if (ff != null && !ff.matches(field)) {
					continue;
				}
				try {
					fc.doWith(field);
				}
				catch (IllegalAccessException ex) {
					throw new IllegalStateException(
							"Shouldn't be illegal to access field '" + field.getName() + "': " + ex);
				}
			}
			targetClass = targetClass.getSuperclass();
		}
		while (targetClass != null && targetClass != Object.class);
	}

	/**
	 * Given the source object and the destination, which must be the same class
	 * or a subclass, copy all fields, including inherited fields. Designed to
	 * work on objects with public no-arg constructors.
	 * @throws IllegalArgumentException if the arguments are incompatible
	 */
	public static void shallowCopyFieldState(final Object src, final Object dest) throws IllegalArgumentException {
		if (src == null) {
			throw new IllegalArgumentException("Source for field copy cannot be null");
		}
		if (dest == null) {
			throw new IllegalArgumentException("Destination for field copy cannot be null");
		}
		if (!src.getClass().isAssignableFrom(dest.getClass())) {
			throw new IllegalArgumentException("Destination class [" + dest.getClass().getName()
					+ "] must be same or subclass as source class [" + src.getClass().getName() + "]");
		}
		doWithFields(src.getClass(), new FieldCallback() {
			public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
				makeAccessible(field);
				Object srcValue = field.get(src);
				field.set(dest, srcValue);
			}
		}, COPYABLE_FIELDS);
	}


	/**
	 * Action to take on each method.
	 */
	public interface MethodCallback {

		/**
		 * Perform an operation using the given method.
		 * @param method the method to operate on
		 */
		void doWith(Method method) throws IllegalArgumentException, IllegalAccessException;
	}


	/**
	 * Callback optionally used to method fields to be operated on by a method callback.
	 */
	public interface MethodFilter {

		/**
		 * Determine whether the given method matches.
		 * @param method the method to check
		 */
		boolean matches(Method method);
	}


	/**
	 * Callback interface invoked on each field in the hierarchy.
	 */
	public interface FieldCallback {

		/**
		 * Perform an operation using the given field.
		 * @param field the field to operate on
		 */
		void doWith(Field field) throws IllegalArgumentException, IllegalAccessException;
	}


	/**
	 * Callback optionally used to filter fields to be operated on by a field callback.
	 */
	public interface FieldFilter {

		/**
		 * Determine whether the given field matches.
		 * @param field the field to check
		 */
		boolean matches(Field field);
	}


	/**
	 * Pre-built FieldFilter that matches all non-static, non-final fields.
	 */
	public static FieldFilter COPYABLE_FIELDS = new FieldFilter() {

		public boolean matches(Field field) {
			return !(Modifier.isStatic(field.getModifiers()) || Modifier.isFinal(field.getModifiers()));
		}
	};


	/**
	 * Pre-built MethodFilter that matches all non-bridge methods.
	 */
	public static MethodFilter NON_BRIDGED_METHODS = new MethodFilter() {

		public boolean matches(Method method) {
			return !method.isBridge();
		}
	};


	/**
	 * Pre-built MethodFilter that matches all non-bridge methods
	 * which are not declared on <code>java.lang.Object</code>.
	 */
	public static MethodFilter USER_DECLARED_METHODS = new MethodFilter() {

		public boolean matches(Method method) {
			return (!method.isBridge() && method.getDeclaringClass() != Object.class);
		}
	};

}
package org.liufei.jweb.reflection;

import java.lang.reflect.Constructor;
import java.util.*;

import org.apache.log4j.Logger;
import org.liufei.jweb.util.ClassUtils;

/**
 * 
 * @author 刘飞
 * 
 */
public class ObjectCreator {
	private final static Logger logger = Logger.getLogger(ObjectCreator.class);

	public final static Object create(String type) {
		try {
			return create(newInstance(type));
		} catch (ClassNotFoundException e) {
			logger.error("class [ " + type + " ] not found .", e);
			throw new RuntimeException(e);
		} catch (LinkageError e) {
			logger.error("LinkageError [ " + type + " ] .", e);
			throw new RuntimeException(e);
		}
	}

	private final static Class<?> newInstance(String type)
			throws ClassNotFoundException, LinkageError {
		return ClassUtils.forName(type, ObjectCreator.class.getClassLoader());
	}

	public final static Object create(Class<?> type) {
		return create(type, null, null);
	}

	public final static Object create(Class<?> type,
			List<Class<?>> constructorArgTypes, List<Object> constructorArgs) {
		Class<?> classToCreate = resolveCollectionInterface(type);
		return instantiateClass(classToCreate, constructorArgTypes,
				constructorArgs);
	}

	private final static Object instantiateClass(Class<?> type,
			List<Class<?>> constructorArgTypes, List<Object> constructorArgs) {
		try {
			Constructor<?> constructor;
			if (constructorArgTypes == null || constructorArgs == null) {
				constructor = type.getDeclaredConstructor();
				if (!constructor.isAccessible()) {
					constructor.setAccessible(true);
				}
				return constructor.newInstance();
			} else {
				constructor = type.getDeclaredConstructor(constructorArgTypes
						.toArray(new Class[constructorArgTypes.size()]));
				if (!constructor.isAccessible()) {
					constructor.setAccessible(true);
				}
				return constructor.newInstance(constructorArgs
						.toArray(new Object[constructorArgs.size()]));
			}
		} catch (Exception e) {
			StringBuilder argTypes = new StringBuilder();
			if (constructorArgTypes != null) {
				for (Class<?> argType : constructorArgTypes) {
					argTypes.append(argType.getSimpleName());
					argTypes.append(",");
				}
			}
			StringBuilder argValues = new StringBuilder();
			if (constructorArgs != null) {
				for (Object argValue : constructorArgs) {
					argValues.append(String.valueOf(argValue));
					argValues.append(",");
				}
			}
			logger.error("Error instantiating " + type
					+ " with invalid types (" + argTypes + ") or values ("
					+ argValues + "). Cause: " + e, e);
			throw new RuntimeException("Error instantiating " + type
					+ " with invalid types (" + argTypes + ") or values ("
					+ argValues + "). Cause: " + e, e);
		}
	}

	private final static Class<?> resolveCollectionInterface(Class<?> type) {
		Class<?> classToCreate;
		if (type == List.class || type == Collection.class) {
			classToCreate = ArrayList.class;
		} else if (type == Map.class) {
			classToCreate = HashMap.class;
		} else if (type == Set.class) {
			classToCreate = HashSet.class;
		} else {
			classToCreate = type;
		}
		return classToCreate;
	}
}

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