GraphTxn.find().forEachRemaining does not close the iterator.

[afs]

Version

5.0.0 development

What happened?

GraphTxn.find returns an etxended iterator that does not get closed properly if exhaused by Iterator.forEachRemaining.

WrappedGraph.forEachRemaining call the wrapped class directly.

Relevant output and stacktrace

public static void main(String... args) {
        Graph g = new GraphTxn();
        ExtendedIterator<Triple> iter = g.find();
        iter.toList();
        //iter.close();
        g.add(SSE.parseTriple("(:s :p :o)"));
    }

Are you interested in making a pull request?

Yes

[afs]

GraphTxn.toList uses ExtendedIterator.forEachRemaining which in WrappedIterator calls the wrapped class and so bypasses GraphTxn.IteratorTxn.hasNext.

ExtendedIterators are best used as: try { ... } finally { iter.close(); } in case the action throws an unexpected exception.

If NiceIterator.asList, which is the code for iter.toList() called forEach, which does call close, instead of forEachRemaining.

The forEachRemaining case still needs fixing.

[afs]

See also #2086, which backports a Jena5 fix to the Jena4 branch.