How to fix leaking this in constructor

Question

i have a class

class Foo { 
   private static Foo foo_obj = null;

   public Foo() {
       if (foo_obj == null) {
           foo = this;
       }
   }
}

I get a warning about leaking this, how would i go about fixing it.

Answer 1

It looks like you are trying to use the singleton pattern. It's an odd way of doing it though and doesn't work. Because each time Foo() gets instantiated, you create a new one. Why not use a more traditional approach like:

class Foo { 
   private static Foo foo_obj = new Foo();
   private Foo() {}
   public static Foo getInstance() { return Foo(); }
}

There are many variations of this pattern on wikipedia.