Use of "this" when a class contains a nested static class

Question

I was going through the following code which is a linked-list implementation using a static nested class:

http://www.cs.cmu.edu/~adamchik/15-121/lectures/Linked%20Lists/code/LinkedList.java

One line I wasn't able to comprehend was:

 public boolean contains(AnyType x)
   {
      **for(AnyType tmp : this)**
         if(tmp.equals(x)) return true;

      return false;
   }

How's it that "this" here allows us to traverse the data that's stored inside each Node?

Answer 1

Because this in this case is an Iterable (more specifically, a LinkedList).

The for-each loop introduced in Java 5, is syntactic sugar for calling the Iterator of the Iterable. In your example case, the code is equivalent with

for (Iterator<AnyType> i = this.iterator(); i.hasNext(); ) {
    if (i.next().equals(x)) return true;
}