| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| /* |
| * $Id: OneStepIteratorForward.java 469314 2006-10-30 23:31:59Z minchau $ |
| */ |
| package org.apache.xpath.axes; |
| |
| import org.apache.xml.dtm.DTM; |
| import org.apache.xml.dtm.DTMFilter; |
| import org.apache.xpath.Expression; |
| import org.apache.xpath.compiler.Compiler; |
| import org.apache.xpath.compiler.OpMap; |
| |
| /** |
| * This class implements a general iterator for |
| * those LocationSteps with only one step, and perhaps a predicate, |
| * that only go forward (i.e. it can not be used with ancestors, |
| * preceding, etc.) |
| * @see org.apache.xpath.axes#ChildTestIterator |
| * @xsl.usage advanced |
| */ |
| public class OneStepIteratorForward extends ChildTestIterator |
| { |
| static final long serialVersionUID = -1576936606178190566L; |
| /** The traversal axis from where the nodes will be filtered. */ |
| protected int m_axis = -1; |
| |
| /** |
| * Create a OneStepIterator object. |
| * |
| * @param compiler A reference to the Compiler that contains the op map. |
| * @param opPos The position within the op map, which contains the |
| * location path expression for this itterator. |
| * |
| * @throws javax.xml.transform.TransformerException |
| */ |
| OneStepIteratorForward(Compiler compiler, int opPos, int analysis) |
| throws javax.xml.transform.TransformerException |
| { |
| super(compiler, opPos, analysis); |
| int firstStepPos = OpMap.getFirstChildPos(opPos); |
| |
| m_axis = WalkerFactory.getAxisFromStep(compiler, firstStepPos); |
| |
| } |
| |
| /** |
| * Create a OneStepIterator object that will just traverse the self axes. |
| * |
| * @param axis One of the org.apache.xml.dtm.Axis integers. |
| * |
| * @throws javax.xml.transform.TransformerException |
| */ |
| public OneStepIteratorForward(int axis) |
| { |
| super(null); |
| |
| m_axis = axis; |
| int whatToShow = DTMFilter.SHOW_ALL; |
| initNodeTest(whatToShow); |
| } |
| |
| |
| |
| |
| /** |
| * Initialize the context values for this expression |
| * after it is cloned. |
| * |
| * @param context The XPath runtime context for this |
| * transformation. |
| */ |
| public void setRoot(int context, Object environment) |
| { |
| super.setRoot(context, environment); |
| m_traverser = m_cdtm.getAxisTraverser(m_axis); |
| |
| } |
| |
| // /** |
| // * Return the first node out of the nodeset, if this expression is |
| // * a nodeset expression. This is the default implementation for |
| // * nodesets. |
| // * <p>WARNING: Do not mutate this class from this function!</p> |
| // * @param xctxt The XPath runtime context. |
| // * @return the first node out of the nodeset, or DTM.NULL. |
| // */ |
| // public int asNode(XPathContext xctxt) |
| // throws javax.xml.transform.TransformerException |
| // { |
| // if(getPredicateCount() > 0) |
| // return super.asNode(xctxt); |
| // |
| // int current = xctxt.getCurrentNode(); |
| // |
| // DTM dtm = xctxt.getDTM(current); |
| // DTMAxisTraverser traverser = dtm.getAxisTraverser(m_axis); |
| // |
| // String localName = getLocalName(); |
| // String namespace = getNamespace(); |
| // int what = m_whatToShow; |
| // |
| // // System.out.println("what: "); |
| // // NodeTest.debugWhatToShow(what); |
| // if(DTMFilter.SHOW_ALL == what |
| // || ((DTMFilter.SHOW_ELEMENT & what) == 0) |
| // || localName == NodeTest.WILD |
| // || namespace == NodeTest.WILD) |
| // { |
| // return traverser.first(current); |
| // } |
| // else |
| // { |
| // int type = getNodeTypeTest(what); |
| // int extendedType = dtm.getExpandedTypeID(namespace, localName, type); |
| // return traverser.first(current, extendedType); |
| // } |
| // } |
| |
| /** |
| * Get the next node via getFirstAttribute && getNextAttribute. |
| */ |
| protected int getNextNode() |
| { |
| m_lastFetched = (DTM.NULL == m_lastFetched) |
| ? m_traverser.first(m_context) |
| : m_traverser.next(m_context, m_lastFetched); |
| return m_lastFetched; |
| } |
| |
| /** |
| * Returns the axis being iterated, if it is known. |
| * |
| * @return Axis.CHILD, etc., or -1 if the axis is not known or is of multiple |
| * types. |
| */ |
| public int getAxis() |
| { |
| return m_axis; |
| } |
| |
| /** |
| * @see Expression#deepEquals(Expression) |
| */ |
| public boolean deepEquals(Expression expr) |
| { |
| if(!super.deepEquals(expr)) |
| return false; |
| |
| if(m_axis != ((OneStepIteratorForward)expr).m_axis) |
| return false; |
| |
| return true; |
| } |
| |
| |
| } |