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An OSGi bundle for Saxon-HE
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2013 Saxonica Limited.
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.evpull;
import net.sf.saxon.trans.XPathException;
/**
* This class is a filter for a sequence of pull events; it returns the input sequence unchanged,
* but traces execution to System.err
*/
public class TracingEventIterator implements EventIterator {
private EventIterator base;
/**
* Create an event iterator that traces all events received from the base sequence, and returns
* them unchanged
* @param base the iterator over the base sequence
*/
public TracingEventIterator(EventIterator base) {
this.base = base;
}
/**
* Determine whether the EventIterator returns a flat sequence of events, or whether it can return
* nested event iterators
*
* @return true if the next() method is guaranteed never to return an EventIterator
*/
public boolean isFlatSequence() {
return base.isFlatSequence();
}
/**
* Get the next event in the sequence
*
* @return the next event, or null when the sequence is exhausted. Note that since an EventIterator is
* itself a PullEvent, this method may return a nested iterator.
* @throws net.sf.saxon.trans.XPathException
* if a dynamic evaluation error occurs
*/
/*@Nullable*/ public PullEvent next() throws XPathException {
PullEvent next = base.next();
if (next == null) {
System.err.println("EVPULL end-of-sequence");
} else {
System.err.println("EVPULL " + next.getClass().getName());
}
return next;
}
}