- /*
- * The Apache Software License, Version 1.1
- *
- *
- * Copyright (c) 1999 The Apache Software Foundation. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. The end-user documentation included with the redistribution,
- * if any, must include the following acknowledgment:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowledgment may appear in the software itself,
- * if and wherever such third-party acknowledgments normally appear.
- *
- * 4. The names "Xalan" and "Apache Software Foundation" must
- * not be used to endorse or promote products derived from this
- * software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache",
- * nor may "Apache" appear in their name, without prior written
- * permission of the Apache Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation and was
- * originally based on software copyright (c) 1999, Lotus
- * Development Corporation., http://www.lotus.com. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- */
- package org.apache.xpath.operations;
-
- import java.util.Vector;
-
- import javax.xml.transform.TransformerException;
- import org.apache.xalan.res.XSLMessages;
- import org.apache.xalan.templates.ElemTemplateElement;
- import org.apache.xalan.templates.ElemVariable;
- import org.apache.xalan.templates.Stylesheet;
- import org.apache.xml.utils.PrefixResolver;
- import org.apache.xml.utils.QName;
- import org.apache.xpath.Expression;
- import org.apache.xpath.ExpressionNode;
- import org.apache.xpath.ExpressionOwner;
- import org.apache.xpath.XPath;
- import org.apache.xpath.XPathContext;
- import org.apache.xpath.XPathVisitor;
- import org.apache.xpath.axes.PathComponent;
- import org.apache.xpath.axes.WalkerFactory;
- import org.apache.xpath.objects.XNodeSet;
- import org.apache.xpath.objects.XObject;
- import org.apache.xpath.res.XPATHErrorResources;
- import org.xml.sax.ContentHandler;
- import org.xml.sax.SAXException;
-
-
- /**
- * The variable reference expression executer.
- */
- public class Variable extends Expression implements PathComponent
- {
- /** Tell if fixupVariables was called.
- * @serial */
- private boolean m_fixUpWasCalled = false;
-
- /** The qualified name of the variable.
- * @serial */
- protected QName m_qname;
-
- /**
- * The index of the variable, which is either an absolute index to a
- * global, or, if higher than the globals area, must be adjusted by adding
- * the offset to the current stack frame.
- */
- protected int m_index;
-
- /**
- * Set the index for the variable into the stack. For advanced use only. You
- * must know what you are doing to use this.
- *
- * @param index a global or local index.
- */
- public void setIndex(int index)
- {
- m_index = index;
- }
-
- /**
- * Set the index for the variable into the stack. For advanced use only.
- *
- * @return index a global or local index.
- */
- public int getIndex()
- {
- return m_index;
- }
-
- /**
- * Set whether or not this is a global reference. For advanced use only.
- *
- * @param isGlobal true if this should be a global variable reference.
- */
- public void setIsGlobal(boolean isGlobal)
- {
- m_isGlobal = isGlobal;
- }
-
- /**
- * Set the index for the variable into the stack. For advanced use only.
- *
- * @return true if this should be a global variable reference.
- */
- public boolean getGlobal()
- {
- return m_isGlobal;
- }
-
-
-
-
-
- protected boolean m_isGlobal = false;
-
- /**
- * This function is used to fixup variables from QNames to stack frame
- * indexes at stylesheet build time.
- * @param vars List of QNames that correspond to variables. This list
- * should be searched backwards for the first qualified name that
- * corresponds to the variable reference qname. The position of the
- * QName in the vector from the start of the vector will be its position
- * in the stack frame (but variables above the globalsTop value will need
- * to be offset to the current stack frame).
- */
- public void fixupVariables(java.util.Vector vars, int globalsSize)
- {
- m_fixUpWasCalled = true;
- int sz = vars.size();
-
- for (int i = vars.size()-1; i >= 0; i--)
- {
- QName qn = (QName)vars.elementAt(i);
- // System.out.println("qn: "+qn);
- if(qn.equals(m_qname))
- {
-
- if(i < globalsSize)
- {
- m_isGlobal = true;
- m_index = i;
- }
- else
- {
- m_index = i-globalsSize;
- }
-
- return;
- }
- }
-
- java.lang.String msg = XSLMessages.createXPATHMessage(XPATHErrorResources.ER_COULD_NOT_FIND_VAR,
- new Object[]{m_qname.toString()});
-
- TransformerException te = new TransformerException(msg, this);
-
- throw new org.apache.xml.utils.WrappedRuntimeException(te);
-
- }
-
-
- /**
- * Set the qualified name of the variable.
- *
- * @param qname Must be a non-null reference to a qualified name.
- */
- public void setQName(QName qname)
- {
- m_qname = qname;
- }
-
- /**
- * Get the qualified name of the variable.
- *
- * @return A non-null reference to a qualified name.
- */
- public QName getQName()
- {
- return m_qname;
- }
-
- /**
- * Execute an expression in the XPath runtime context, and return the
- * result of the expression.
- *
- *
- * @param xctxt The XPath runtime context.
- *
- * @return The result of the expression in the form of a <code>XObject</code>.
- *
- * @throws javax.xml.transform.TransformerException if a runtime exception
- * occurs.
- */
- public XObject execute(XPathContext xctxt)
- throws javax.xml.transform.TransformerException
- {
- return execute(xctxt, false);
- }
-
-
- /**
- * Dereference the variable, and return the reference value. Note that lazy
- * evaluation will occur. If a variable within scope is not found, a warning
- * will be sent to the error listener, and an empty nodeset will be returned.
- *
- *
- * @param xctxt The runtime execution context.
- *
- * @return The evaluated variable, or an empty nodeset if not found.
- *
- * @throws javax.xml.transform.TransformerException
- */
- public XObject execute(XPathContext xctxt, boolean destructiveOK) throws javax.xml.transform.TransformerException
- {
- org.apache.xml.utils.PrefixResolver xprefixResolver = xctxt.getNamespaceContext();
-
- // Is the variable fetched always the same?
- // XObject result = xctxt.getVariable(m_qname);
- if(m_fixUpWasCalled)
- {
- XObject result;
- if(m_isGlobal)
- result = xctxt.getVarStack().getGlobalVariable(xctxt, m_index, destructiveOK);
- else
- result = xctxt.getVarStack().getLocalVariable(xctxt, m_index, destructiveOK);
-
- if (null == result)
- {
- // This should now never happen...
- warn(xctxt, XPATHErrorResources.WG_ILLEGAL_VARIABLE_REFERENCE,
- new Object[]{ m_qname.getLocalPart() }); //"VariableReference given for variable out "+
- // (new RuntimeException()).printStackTrace();
- // error(xctxt, XPATHErrorResources.ER_COULDNOT_GET_VAR_NAMED,
- // new Object[]{ m_qname.getLocalPart() }); //"Could not get variable named "+varName);
-
- result = new XNodeSet(xctxt.getDTMManager());
- }
-
- return result;
- }
- else
- {
- // Hack city... big time. This is needed to evaluate xpaths from extensions,
- // pending some bright light going off in my head. Some sort of callback?
- synchronized(this)
- {
- org.apache.xalan.templates.ElemVariable vvar= getElemVariable();
- if(null != vvar)
- {
- m_index = vvar.getIndex();
- m_isGlobal = vvar.getIsTopLevel();
- m_fixUpWasCalled = true;
- return execute(xctxt);
- }
- }
- throw new javax.xml.transform.TransformerException(XSLMessages.createXPATHMessage(XPATHErrorResources.ER_VAR_NOT_RESOLVABLE, new Object[]{m_qname.toString()})); //"Variable not resolvable: "+m_qname);
- }
- }
-
- /**
- * Get the XSLT ElemVariable that this sub-expression references. In order for
- * this to work, the SourceLocator must be the owning ElemTemplateElement.
- * @return The dereference to the ElemVariable, or null if not found.
- */
- public org.apache.xalan.templates.ElemVariable getElemVariable()
- {
-
- // Get the current ElemTemplateElement, and then walk backwards in
- // document order, searching
- // for an xsl:param element or xsl:variable element that matches our
- // qname. If we reach the top level, use the StylesheetRoot's composed
- // list of top level variables and parameters.
-
- org.apache.xpath.ExpressionNode owner = getExpressionOwner();
-
- if (null != owner && owner instanceof org.apache.xalan.templates.ElemTemplateElement)
- {
-
- org.apache.xalan.templates.ElemVariable vvar;
-
- org.apache.xalan.templates.ElemTemplateElement prev =
- (org.apache.xalan.templates.ElemTemplateElement) owner;
-
- if (!(prev instanceof org.apache.xalan.templates.Stylesheet))
- {
- while ( !(prev.getParentNode() instanceof org.apache.xalan.templates.Stylesheet) )
- {
- org.apache.xalan.templates.ElemTemplateElement savedprev = prev;
-
- while (null != (prev = prev.getPreviousSiblingElem()))
- {
- if(prev instanceof org.apache.xalan.templates.ElemVariable)
- {
- vvar = (org.apache.xalan.templates.ElemVariable) prev;
-
- if (vvar.getName().equals(m_qname))
- {
- return vvar;
- }
- }
- }
- prev = savedprev.getParentElem();
- }
- }
-
- vvar = prev.getStylesheetRoot().getVariableOrParamComposed(m_qname);
- if (null != vvar)
- {
- return vvar;
- }
-
- }
- return null;
-
- }
-
- /**
- * Tell if this expression returns a stable number that will not change during
- * iterations within the expression. This is used to determine if a proximity
- * position predicate can indicate that no more searching has to occur.
- *
- *
- * @return true if the expression represents a stable number.
- */
- public boolean isStableNumber()
- {
- return true;
- }
-
- /**
- * Get the analysis bits for this walker, as defined in the WalkerFactory.
- * @return One of WalkerFactory#BIT_DESCENDANT, etc.
- */
- public int getAnalysisBits()
- {
- org.apache.xalan.templates.ElemVariable vvar = getElemVariable();
- if(null != vvar)
- {
- XPath xpath = vvar.getSelect();
- if(null != xpath)
- {
- Expression expr = xpath.getExpression();
- if(null != expr && expr instanceof PathComponent)
- {
- return ((PathComponent)expr).getAnalysisBits();
- }
- }
- }
- return WalkerFactory.BIT_FILTER;
- }
-
-
- /**
- * @see XPathVisitable#callVisitors(ExpressionOwner, XPathVisitor)
- */
- public void callVisitors(ExpressionOwner owner, XPathVisitor visitor)
- {
- visitor.visitVariableRef(owner, this);
- }
-
- /**
- * @see Expression#deepEquals(Expression)
- */
- public boolean deepEquals(Expression expr)
- {
- if(!isSameClass(expr))
- return false;
-
- if(!m_qname.equals(((Variable)expr).m_qname))
- return false;
-
- // We have to make sure that the qname really references
- // the same variable element.
- if(getElemVariable() != ((Variable)expr).getElemVariable())
- return false;
-
- return true;
- }
-
- static final java.lang.String PSUEDOVARNAMESPACE = "http://xml.apache.org/xalan/psuedovar";
-
- /**
- * Tell if this is a psuedo variable reference, declared by Xalan instead
- * of by the user.
- */
- public boolean isPsuedoVarRef()
- {
- java.lang.String ns = m_qname.getNamespaceURI();
- if((null != ns) && ns.equals(PSUEDOVARNAMESPACE))
- {
- if(m_qname.getLocalName().startsWith("#"))
- return true;
- }
- return false;
- }
-
-
- }