public static class DistinctValues.DistinctIterator extends java.lang.Object implements SequenceIterator
SequenceIterator.Property
Constructor and Description |
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DistinctIterator(SequenceIterator base,
StringCollator collator,
XPathContext context)
Create an iterator over the distinct values in a sequence
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Modifier and Type | Method and Description |
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void |
close()
Close the iterator.
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AtomicValue |
next()
Get the next item in the sequence.
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clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
forEachOrFail, getProperties, materialize
public DistinctIterator(SequenceIterator base, StringCollator collator, XPathContext context)
base
- the input sequence. This must return atomic values only.collator
- The comparer used to obtain comparison keys from each value;
these comparison keys are themselves compared using equals().context
- the XPath dynamic contextpublic AtomicValue next() throws XPathException
next
in interface SequenceIterator
XPathException
- if an error occurs retrieving the next itempublic void close()
SequenceIterator
For example, the iterator returned by the unparsed-text-lines() function has a close() method that causes the underlying input stream to be closed, whether or not the file has been read to completion.
Closing an iterator is important when the data is being "pushed" in another thread. Closing the iterator terminates that thread and means that it needs to do no additional work. Indeed, failing to close the iterator may cause the push thread to hang waiting for the buffer to be emptied.
close
in interface java.io.Closeable
close
in interface java.lang.AutoCloseable
close
in interface SequenceIterator
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