String is immutable - practical check-up

stringIs.java

String t = "foo"; //  newer obj created and added string pool
System.out.println("hashCode of t: " + t.hashCode());

t = "foo";  //  shares the same memory location - same hashCode()
System.out.println("hashCode of 2 t: " + t.hashCode());

t = "fuc";  //  newer value added - newer obj created and added string pool - different hashCode()
System.out.println("hashCode of 3 t: " + t.hashCode());

t = new String("foo");  //  shares the same memory location - same hashCode()
System.out.println("hashCode of 4 t: " + t.hashCode());

t = new StringBuilder("foo").toString();  //  shares the same memory location - same hashCode()
System.out.println("hashCode of 5 t: " + t.hashCode());

//  o/p is
hashCode of t: 101574
hashCode of 2 t: 101574
hashCode of 3 t: 101748
hashCode of 4 t: 101574
hashCode of 5 t: 101574