Java - when “this” is the only way to go?

Question

The following code runs for both var = putVar; & this.var = putVar;

I understand: \"this\" is used to identify that - \"put this value for just \'my\'

Answer 1

There are 2 cases I know of, aside from the case ktm mentioned (which I think is obvious and you already knew):

1. Just to make it very clear that they're referring to the member of the current object.

   void foo(int x) {
       this.y = x; // No mistaking that y belongs to the object
   }
   

2. If you're in an anonymous inner class within another object (ex: of class ClassName), you can use ClassName.this to get the instance of the enclosing object. The reason for this (no pun intended) is that, inside the inner class, this will refer to the inner class.

   SomeInnerClass myObj = new SomeInnerClass() {
       void bar() {
           this.y = 0; // this refers to the SomeInnerClass object
           OuterClass.this.y = 0; // OuterClass.this refers to the enclosing class OuterClass object
       }
   };