java类型

the types of the java programming language are divided into two categories:

• primitive types
• reference types

the primitive types are the boolean type and the numeric types.

the numeric types are the integral types byte ,short, int, long, and char, and the floating-point types float and double.

8种基本类型：boolean byte short int long char float double

the reference types are class types, interface types, and array types.

there is also a special null type.

an object is a dynamically created instance of a class type or a dynamically created array.the values of a reference type are references to objects.

all objects, including arrays, support the methods of class object.

string literals are represented by string objects.