包装类--(1)

public class MyTest2 {
    public static void main(String[] args) {
        Integer i1 = Integer.valueOf(10);
        Integer i2 = Integer.valueOf(10);
        System.out.println(i1 == i2);//t
        System.out.println(i1.equals(i2));//t
        System.out.println("++++++++++++++++++++++++++++");
        Integer i3 = Integer.valueOf(127);
        Integer i4 = Integer.valueOf(127);
        System.out.println(i3 == i4);//t
        System.out.println(i3.equals(i4));//t
        System.out.println("++++++++++++++++++++++++++++");
        Integer i5 = Integer.valueOf(128);
        Integer i6 = Integer.valueOf(128);
        System.out.println(i5 == i6);//f
        System.out.println(i5.equals(i6));//t
        System.out.println("++++++++++++++++++++++++++++");
        Integer i7 = Integer.valueOf(-128);
        Integer i8 = Integer.valueOf(-128);
        System.out.println(i7 == i8);//t
        System.out.println(i7.equals(i8));//t
        System.out.println("++++++++++++++++++++++++++++");
        Integer i9 = Integer.valueOf(-129);
        Integer i10 = Integer.valueOf(-129);
        System.out.println(i9 == i10);//f
        System.out.println(i9.equals(i10));//t
        System.out.println("++++++++++++++++++++++++++++");
        Integer i11 = 10;
        Integer i12 = 10;
        System.out.println(i1 == i12);//t
        System.out.println(i11.equals(i12));//t
    }
}

 

* 包装类 -类
* 1.目前存在的问题?
* 8种基本数据类型无法当成引用数据类型使用的问题
* 2.如何解决上面的问题?
* 想一种方式将8种基本数据类型无法当成引用数据类型使用的问题
* 包装类可以解决
* 3.包装类 -8种
* byte Byte
* short Short
* int Integer
* long Long
* double Double
* char Character
* boolean Boolean

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