Is Java Pass by Reference or Pass by Value?

Java always pass by value. It confuses when we pass an object reference in method call and method implementation changes objects attributes. When we see these changes after returning from method call it feels like java use pass by reference but its not true. Java uses pass by value and mthod try to change value it will not reflect after call. Changing value means re-initianciation . The first case is referenced values got mutated but it was still pass by value.

It goes like this:

public void foo(User user) {
  user.name.equals("Mayank"); // true
  user = new User("Mike");
  d.name.equals("Mike"); // true
}

User user1 = new User("Mayank");
foo(user1);
user1.name.equals("Mayank"); // still true

In this example user1.name will still be "Mayank". "user" is not overwritten in the function as the object reference is passed by value.

Likewise:

public void foo(USer user) {
  user.name.equals("Mayank"); // true
  user.setname("Mike");
}

User user1 = new Use("Mayank");
foo(user1);

user1.name.equals("Mayank"); // Not true anymore as name got mutated 

user1.name.equals("Mike"); // true

For further details please see this link
http://stackoverflow.com/questions/40480/is-java-pass-by-reference