Int wrapper class Integer "=="

1. The value is different, use == and equals comparison both return false

2. If the value is the same, use == comparison: basic type-basic type, basic type-package object returns true

                                             Wrapped object-wrapped object returns false

Some common Integer objects in jdk cache:

           Integer i1 = 100;
            Integer i2 = 100;
            Integer i3 = 150;
            Integer i4 = 150;
             
            System.out.println(i1==i2); //打印true
            System.out.println(i3==i4); //打印false

         The reason is as follows: Integer has a buffer area that will cache the number between 127 and -128, so the result of i1==i2 is true