[COLLECTIONS-111] IteratorChain skips over elements in iterator

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Cannot Reproduce
• Affects Version/s: 3.1
• Component/s: Iterator

Environment

Operating System: Windows XP
Platform: PC

• Bugzilla Id: 38341
• Assignee: Unassigned
• Reporter: Jonathan Giles
• Created: 21/Jan/06 10:12
• Updated: 28/Feb/13 19:52
• Resolved: 19/Mar/08 06:52

Description

Hi there,
When using the IteratorChain class to add multiple iterators, it appears that
using itChain.hasNext() and itChain.next() skips a number of elements in the
iterator at each step.

Given a single iterator of 7 elements, and using the following code:

private IteratorChain buildIterator() {
// this iterator contains the children of the current object only
Iterator it = getChildren(p);

// we use an IteratorChain to add multiple iterators together without the
overhead of copying
IteratorChain itChain = new IteratorChain(it);

return itChain;
}

and then simply
IteratorChain it = treeModel.getAllTreeNodes(obj);

// FIXME this only prints one or two of the results, which is a bug!
while (it.hasNext())
System.out.println(": " + it.next().getClass());

I put in 7 elements, but only get 2 out - the 2nd and the last elements. It
appears that through my debugging that the nextClause variable is updated even
when the hasNext() function is called.

Also, if I put 7 system.out.println statements, all elements are printed as normal.