package net.sf.saxon.tree;
import net.sf.saxon.om.*;
import net.sf.saxon.pattern.NameTest;
import net.sf.saxon.pattern.NodeTest;
import net.sf.saxon.type.Type;
/**
* AttributeEnumeration is an enumeration of all the attribute nodes of an Element.
*/
final class AttributeEnumeration extends AxisIteratorImpl implements LookaheadIterator {
private ElementImpl element;
private NodeTest nodeTest;
private NodeInfo next;
private int index;
private int length;
/**
* Constructor
* @param node: the element whose attributes are required. This may be any type of node,
* but if it is not an element the enumeration will be empty
* @param nodeTest: condition to be applied to the names of the attributes selected
*/
public AttributeEnumeration(NodeImpl node, NodeTest nodeTest) {
this.nodeTest = nodeTest;
if (node.getNodeKind()==Type.ELEMENT) {
element = (ElementImpl)node;
AttributeCollection attlist = element.getAttributeList();
index = 0;
if (nodeTest instanceof NameTest) {
NameTest test = (NameTest)nodeTest;
index = attlist.getIndexByFingerprint(test.getFingerprint());
if (index<0) {
next = null;
} else {
next = new AttributeImpl(element, index);
index = 0;
length = 0; // force iteration to select one node only
}
} else {
index = 0;
length = attlist.getLength();
advance();
}
}
else { // if it's not an element, or if we're not looking for attributes,
// then there's nothing to find
next = null;
index = 0;
length = 0;
}
}
/**
* Test if there are mode nodes still to come.
* ("elements" is used here in the sense of the Java enumeration class, not in the XML sense)
*/
public boolean hasNext() {
return next != null;
}
/**
* Get the next node in the iteration, or null if there are no more.
*/
public Item next() {
if (next == null) {
current = null;
position = -1;
return null;
} else {
current = next;
position++;
advance();
return current;
}
}
/**
* Move to the next node in the enumeration.
*/
private void advance() {
do {
if (index<length) {
next = new AttributeImpl(element, index);
index++;
} else {
next = null;
return;
}
} while (!nodeTest.matches(next));
}
/**
* Get another enumeration of the same nodes
*/
public SequenceIterator getAnother() {
return new AttributeEnumeration(element, nodeTest);
}
/**
* Get properties of this iterator, as a bit-significant integer.
*
* @return the properties of this iterator. This will be some combination of
* properties such as {@link GROUNDED}, {@link LAST_POSITION_FINDER},
* and {@link LOOKAHEAD}. It is always
* acceptable to return the value zero, indicating that there are no known special properties.
* It is acceptable for the properties of the iterator to change depending on its state.
*/
public int getProperties() {
return LOOKAHEAD;
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (the "License");
// you may not use this file except in compliance with the License. You may obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
//