/*
* 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
{
/**
* Constructor ElemVariable
*
*/
public ElemVariable(){}
/**
* 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;
/**
* Sets the relative position of this variable within the stack frame (if local)
* or the global area (if global). Note that this should be called only for
* global variables since the local position is computed in the compose() method.
*/
public void setIndex(int index)
{
m_index = index;
}
/**
* If this element is not at the top-level, get the relative position of the
* variable into the stack frame. If this variable is at the top-level, get
* the relative position within the global area.
*/
public int getIndex()
{
return m_index;
}
/**
* 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;
}
}