Priority Queue problem

Question

Hi Everybody.
Can anyone tell me in which order elements of priority queue are sorted.
I have used following code
class Test{
PriorityQueue <strings> pq=new PriorityQueue <Strings>();
pq.add("silpa");
pq.add("swati");
pq.add("roopa");
pq.add("abc");
System.out.println(pq);
System.out.println(pq.poll());
System.out.println(pq.peak());
The output I got is
[abc silpa swathi roopa]
abc
roopa.
Can anybody explain why the collection elements are not sorted ?
I am getting correct output with peek() n poll().According that methods i should get
[abc roopa silpa swathi ]
Explain the reason?

Answer 1

System.out.println(pq);This line prints out the contents of the queue, by implicitly calling pq.toString(), whose behaviour is inherited from AbstractCollection, which therefore has nothing to do with sorting. So you have no valid reason for expecting any particular ordering.