/-----------关键字：integer缓存

 1 public class TestInteger {
 2     public static void main(String[] args){
 3         Integer i1 = 127;
 4         Integer i2 = 127;
 5         System.out.println(i1==i2);
 6         
 7         Integer i3 = 128;
 8         Integer i4 = 128;
 9         System.out.println(i3==i4);
10         
11         Integer i5 = -128;
12         Integer i6 = -128;
13         System.out.println(i5==i6);
14         
15         Integer i7 = -129;
16         Integer i8 = -129;
17         System.out.println(i7==i8);
18     }
19 }