Java integer constant Pool __java

Similar to string pool, there is a pool of integers (integer objects, not basic types) in Java. In Java, integers (0-127) within 1 byte sizes exist in a constant pool (not including new Integer (XX) initialization), so their references are the same.

1. Initializing with an equal sign and a basic type is equivalent to initializing with "=" and a constant, the code is as follows,

The output is as follows: 127 are equal references before.

2. Contrast code

The results are as follows: You can see that the results are false. Because one of these is not a value in a constant pool.