java 数据类型

char byte short int long float longlong double  obj

char byte short 在算术运算时会自动转换为int类型计算
type.MAX_VALUE //type是容器类型 如Integer.MAX_VALUE 输出int最大值

 

//: initializtion/PrimitiveOverLoading.java
package object;

import static net.mindview.util.Print.*;

public class PrimitiveOverLoading
{
    void f1(char x){printnb("f1(char)");}
    void f1(byte x){printnb("f1(byte)");}
    void f1(short x){printnb("f1(short)");}
    void f1(int x){printnb("f1(int)");}
    void f1(long x){printnb("f1(long)");}
    void f1(float x){printnb("f1(float");}
    void f1(double x){printnb("f1(double)");}
    
    void f2(byte x){printnb("f2(byte)");}
    void f2(short x){printnb("f2(short)");}
    void f2(int x){printnb("f2(int)");}
    void f2(long x){printnb("f2(long)");}
    void f2(float x){printnb("f2(float");}
    void f2(double x){printnb("f2(double)");}
    
    void f3(short x){printnb("f3(short)");}
    void f3(int x){printnb("f3(int)");}
    void f3(long x){printnb("f3(long)");}
    void f3(float x){printnb("f3(float");}
    void f3(double x){printnb("f3(double)");}
    
    void f4(int x){printnb("f4(int)");}
    void f4(long x){printnb("f4(long)");}
    void f4(float x){printnb("f4(float");}
    void f4(double x){printnb("f4(double)");}
    
    void f5(long x){printnb("f5(long)");}
    void f5(float x){printnb("f5(float");}
    void f5(double x){printnb("f5(double)");}
    
    void f6(float x){printnb("f6(float");}
    void f6(double x){printnb("f6(double)");}
    
    void f7(double x){printnb("f7(double)");}
    
    void testConstVal(){
        printnb("5: ");
        f1(5);f2(5);f3(5);f4(5);f6(5);f7(5); print();
    }
    void testChar(){
        char x = 0;
        printnb("char: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testByte(){
        byte x= 0;
        printnb("byte: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testShort(){
        short x= 0;
        printnb("short : ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testInt(){
        int x= 0;
        printnb("int: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testLong(){
        long x= 0;
        printnb("long: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testFloat(){
        float x= 0;
        printnb("Float: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    void testDouble(){
        double x= 0;
        printnb("double: ");
        f1(x);f2(x);f3(x);f4(x);f6(x);f7(x); print();
    }
    public static void main(String[] args)
    {
        PrimitiveOverLoading p = new PrimitiveOverLoading();
        p.testConstVal(); //常数值5被int 处理,如果传入类型不符合,就会进行提升和强制窄化处理
        p.testChar();     //char 如果没有接受char 的方法 就会直接 提升到int 
        p.testByte();
        p.testShort();
        p.testInt();
        p.testLong();
        p.testFloat();
        p.testDouble();
    }
} /* output:
5: f1(int)f2(int)f3(int)f4(int)f6(floatf7(double)
char: f1(char)f2(int)f3(int)f4(int)f6(floatf7(double)
byte: f1(byte)f2(byte)f3(short)f4(int)f6(floatf7(double)
short : f1(short)f2(short)f3(short)f4(int)f6(floatf7(double)
int: f1(int)f2(int)f3(int)f4(int)f6(floatf7(double)
long: f1(long)f2(long)f3(long)f4(long)f6(floatf7(double)
Float: f1(floatf2(floatf3(floatf4(floatf6(floatf7(double)
double: f1(double)f2(double)f3(double)f4(double)f6(double)f7(double)
*///~