/* * 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.xalan.templates; //import org.w3c.dom.*; import org.apache.xml.dtm.DTM; import org.xml.sax.*; import org.apache.xpath.*; import org.apache.xpath.objects.XObject; import org.apache.xpath.objects.XString; import org.apache.xpath.objects.XRTreeFrag; import org.apache.xpath.objects.XRTreeFragSelectWrapper; import org.apache.xml.utils.QName; import org.apache.xalan.trace.SelectionEvent; import org.apache.xalan.res.XSLTErrorResources; import org.apache.xalan.transformer.TransformerImpl; import javax.xml.transform.TransformerException; /** * <meta name="usage" content="advanced"/> * Implement xsl:variable. * <pre> * <!ELEMENT xsl:variable %template;> * <!ATTLIST xsl:variable * name %qname; #REQUIRED * select %expr; #IMPLIED * > * </pre> * @see <a href="http://www.w3.org/TR/xslt#variables">variables in XSLT Specification</a> */ public class ElemVariable extends ElemTemplateElement { /** * This is the index into the stack frame. If the index is above the * global area, it will have to be offset at execution time. */ protected int m_index; // Get the relative index of this variable. public int getIndex() { return m_index; } /** * Constructor ElemVariable * */ public ElemVariable(){} /** * The value of the "select" attribute. * @serial */ private XPath m_selectPattern; /** * Set the "select" attribute. * If the variable-binding element has a select attribute, * then the value of the attribute must be an expression and * the value of the variable is the object that results from * evaluating the expression. In this case, the content * of the variable must be empty. * * @param v Value to set for the "select" attribute. */ public void setSelect(XPath v) { m_selectPattern = v; } /** * Get the "select" attribute. * If the variable-binding element has a select attribute, * then the value of the attribute must be an expression and * the value of the variable is the object that results from * evaluating the expression. In this case, the content * of the variable must be empty. * * @return Value of the "select" attribute. */ public XPath getSelect() { return m_selectPattern; } /** * The value of the "name" attribute. * @serial */ protected QName m_qname; /** * Set the "name" attribute. * Both xsl:variable and xsl:param have a required name * attribute, which specifies the name of the variable. The * value of the name attribute is a QName, which is expanded * as described in [2.4 Qualified Names]. * @see <a href="http://www.w3.org/TR/xslt#qname">qname in XSLT Specification</a> * * @param v Value to set for the "name" attribute. */ public void setName(QName v) { m_qname = v; } /** * Get the "name" attribute. * Both xsl:variable and xsl:param have a required name * attribute, which specifies the name of the variable. The * value of the name attribute is a QName, which is expanded * as described in [2.4 Qualified Names]. * @see <a href="http://www.w3.org/TR/xslt#qname">qname in XSLT Specification</a> * * @return Value of the "name" attribute. */ public QName getName() { return m_qname; } /** * Tells if this is a top-level variable or param, or not. * @serial */ private boolean m_isTopLevel = false; /** * Set if this is a top-level variable or param, or not. * @see <a href="http://www.w3.org/TR/xslt#top-level-variables">top-level-variables in XSLT Specification</a> * * @param v Boolean indicating whether this is a top-level variable * or param, or not. */ public void setIsTopLevel(boolean v) { m_isTopLevel = v; } /** * Get if this is a top-level variable or param, or not. * @see <a href="http://www.w3.org/TR/xslt#top-level-variables">top-level-variables in XSLT Specification</a> * * @return Boolean indicating whether this is a top-level variable * or param, or not. */ public boolean getIsTopLevel() { return m_isTopLevel; } /** * Get an integer representation of the element type. * * @return An integer representation of the element, defined in the * Constants class. * @see org.apache.xalan.templates.Constants */ public int getXSLToken() { return Constants.ELEMNAME_VARIABLE; } /** * Return the node name. * * @return The node name */ public String getNodeName() { return Constants.ELEMNAME_VARIABLE_STRING; } /** * Copy constructor. * * @param param An element created from an xsl:variable * * @throws TransformerException */ public ElemVariable(ElemVariable param) throws TransformerException { m_selectPattern = param.m_selectPattern; m_qname = param.m_qname; m_isTopLevel = param.m_isTopLevel; // m_value = param.m_value; // m_varContext = param.m_varContext; } /** * Execute a variable declaration and push it onto the variable stack. * @see <a href="http://www.w3.org/TR/xslt#variables">variables in XSLT Specification</a> * * @param transformer non-null reference to the the current transform-time state. * @param sourceNode non-null reference to the <a href="http://www.w3.org/TR/xslt#dt-current-node">current source node</a>. * @param mode reference, which may be null, to the <a href="http://www.w3.org/TR/xslt#modes">current mode</a>. * * @throws TransformerException */ public void execute(TransformerImpl transformer) throws TransformerException { if (TransformerImpl.S_DEBUG) transformer.getTraceManager().fireTraceEvent(this); int sourceNode = transformer.getXPathContext().getCurrentNode(); XObject var = getValue(transformer, sourceNode); // transformer.getXPathContext().getVarStack().pushVariable(m_qname, var); transformer.getXPathContext().getVarStack().setLocalVariable(m_index, var); } /** * Get the XObject representation of the variable. * * @param transformer non-null reference to the the current transform-time state. * @param sourceNode non-null reference to the <a href="http://www.w3.org/TR/xslt#dt-current-node">current source node</a>. * * @return the XObject representation of the variable. * * @throws TransformerException */ public XObject getValue(TransformerImpl transformer, int sourceNode) throws TransformerException { XObject var; XPathContext xctxt = transformer.getXPathContext(); xctxt.pushCurrentNode(sourceNode); try { if (null != m_selectPattern) { var = m_selectPattern.execute(xctxt, sourceNode, this); var.allowDetachToRelease(false); if (TransformerImpl.S_DEBUG) transformer.getTraceManager().fireSelectedEvent(sourceNode, this, "select", m_selectPattern, var); } else if (null == getFirstChildElem()) { var = XString.EMPTYSTRING; } else { // Use result tree fragment int df = transformer.transformToRTF(this); var = new XRTreeFrag(df, xctxt); } } finally { xctxt.popCurrentNode(); } return var; } /** * This function is called after everything else has been * recomposed, and allows the template to set remaining * values that may be based on some other property that * depends on recomposition. */ public void compose(StylesheetRoot sroot) throws TransformerException { // See if we can reduce an RTF to a select with a string expression. if(null == m_selectPattern && org.apache.xalan.processor.TransformerFactoryImpl.m_optimize) { XPath newSelect = rewriteChildToExpression(this); if(null != newSelect) m_selectPattern = newSelect; } StylesheetRoot.ComposeState cstate = sroot.getComposeState(); // This should be done before addVariableName, so we don't have visibility // to the variable now being defined. java.util.Vector vnames = cstate.getVariableNames(); if(null != m_selectPattern) m_selectPattern.fixupVariables(vnames, cstate.getGlobalsSize()); // Only add the variable if this is not a global. If it is a global, // it was already added by stylesheet root. if(!(m_parentNode instanceof Stylesheet)) m_index = cstate.addVariableName(m_qname) - cstate.getGlobalsSize(); // This has to be done after the addVariableName, so that the variable // pushed won't be immediately popped again in endCompose. super.compose(sroot); } // /** // * This after the template's children have been composed. // */ // public void endCompose() throws TransformerException // { // super.endCompose(); // } /** * If the children of a variable is a single xsl:value-of or text literal, * it is cheaper to evaluate this as an expression, so try and adapt the * child an an expression. * * @param varElem Should be a ElemParam, ElemVariable, or ElemWithParam. * * @return An XPath if rewrite is possible, else null. * * @throws TransformerException */ static XPath rewriteChildToExpression(ElemTemplateElement varElem) throws TransformerException { ElemTemplateElement t = varElem.getFirstChildElem(); // Down the line this can be done with multiple string objects using // the concat function. if (null != t && null == t.getNextSiblingElem()) { int etype = t.getXSLToken(); if (Constants.ELEMNAME_VALUEOF == etype) { ElemValueOf valueof = (ElemValueOf) t; // %TBD% I'm worried about extended attributes here. if (valueof.getDisableOutputEscaping() == false && valueof.getDOMBackPointer() == null) { varElem.m_firstChild = null; return new XPath(new XRTreeFragSelectWrapper(valueof.getSelect().getExpression())); } } else if (Constants.ELEMNAME_TEXTLITERALRESULT == etype) { ElemTextLiteral lit = (ElemTextLiteral) t; if (lit.getDisableOutputEscaping() == false && lit.getDOMBackPointer() == null) { String str = lit.getNodeValue(); XString xstr = new XString(str); varElem.m_firstChild = null; return new XPath(new XRTreeFragSelectWrapper(xstr)); } } } return null; } /** * This function is called during recomposition to * control how this element is composed. * @param root The root stylesheet for this transformation. */ public void recompose(StylesheetRoot root) { root.recomposeVariables(this); } /** * Set the parent as an ElemTemplateElement. * * @param parent This node's parent as an ElemTemplateElement */ public void setParentElem(ElemTemplateElement p) { super.setParentElem(p); p.m_hasVariableDecl = true; } }