Why Hash Code of different Boolean instances is always the same?

Question

In the below code, the hash code is always same. Why is it like that?

Code:

public class BooleanClass {      public static void main(String[] args) {         Boolean b1 = new Boolean(true);         Boolean b2 = new Boolean(false);         Boolean b3 = new Boolean(true);         Boolean b4 = new Boolean(false);         Boolean b5 = new Boolean(false);         Boolean b6 = new Boolean(true);          System.out.println(b1.hashCode());         System.out.println(b2.hashCode());         System.out.println(b3.hashCode());         System.out.println(b4.hashCode());         System.out.println(b5.hashCode());         System.out.println(b6.hashCode());     } } 

Output:

1231 1237 1231 1237 1237 1231 

Always the same numbers 1231 and 1237 are printed. Any reason?

Answer 1

The JavaDoc of Boolean.hashCode() method says:

Returns the integer 1231 if this object represents true; returns the integer 1237 if this object represents false.