- /*
- * Copyright 1999-2004 The Apache Software Foundation.
- *
- * Licensed 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.
- */
- package com.sun.org.apache.xpath.internal.operations;
-
- import javax.xml.transform.TransformerException;
-
- import com.sun.org.apache.xalan.internal.res.XSLMessages;
- import com.sun.org.apache.xml.internal.utils.QName;
- import com.sun.org.apache.xpath.internal.Expression;
- import com.sun.org.apache.xpath.internal.ExpressionOwner;
- import com.sun.org.apache.xpath.internal.XPath;
- import com.sun.org.apache.xpath.internal.XPathContext;
- import com.sun.org.apache.xpath.internal.XPathVisitor;
- import com.sun.org.apache.xpath.internal.axes.PathComponent;
- import com.sun.org.apache.xpath.internal.axes.WalkerFactory;
- import com.sun.org.apache.xpath.internal.objects.XNodeSet;
- import com.sun.org.apache.xpath.internal.objects.XObject;
- import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
-
-
- /**
- * 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 com.sun.org.apache.xml.internal.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
- {
- com.sun.org.apache.xml.internal.utils.PrefixResolver xprefixResolver = xctxt.getNamespaceContext();
-
- XObject result;
-
- // Is the variable fetched always the same?
- // XObject result = xctxt.getVariable(m_qname);
- if(m_fixUpWasCalled)
- {
- if(m_isGlobal)
- result = xctxt.getVarStack().getGlobalVariable(xctxt, m_index, destructiveOK);
- else
- result = xctxt.getVarStack().getLocalVariable(xctxt, m_index, destructiveOK);
- } else {
- result = xctxt.getVarStack().getVariableOrParam(xctxt,m_qname);
- }
-
- 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)
- // {
- // com.sun.org.apache.xalan.internal.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 com.sun.org.apache.xalan.internal.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.
-
- com.sun.org.apache.xpath.internal.ExpressionNode owner = getExpressionOwner();
-
- if (null != owner && owner instanceof com.sun.org.apache.xalan.internal.templates.ElemTemplateElement)
- {
-
- com.sun.org.apache.xalan.internal.templates.ElemVariable vvar;
-
- com.sun.org.apache.xalan.internal.templates.ElemTemplateElement prev =
- (com.sun.org.apache.xalan.internal.templates.ElemTemplateElement) owner;
-
- if (!(prev instanceof com.sun.org.apache.xalan.internal.templates.Stylesheet))
- {
- while ( !(prev.getParentNode() instanceof com.sun.org.apache.xalan.internal.templates.Stylesheet) )
- {
- com.sun.org.apache.xalan.internal.templates.ElemTemplateElement savedprev = prev;
-
- while (null != (prev = prev.getPreviousSiblingElem()))
- {
- if(prev instanceof com.sun.org.apache.xalan.internal.templates.ElemVariable)
- {
- vvar = (com.sun.org.apache.xalan.internal.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()
- {
- // <<<<<<< TIGER SPECIFIC CHANGE >>>>>>>>>
- // As we are not supporting Xalan interpretive we are taking away the functionality
- // dependent on XSLT interpretive Transformer. Only way supported is to use XSLTC
- // and the execution path needed for supporting standard XPath API defined by
- // JAXP 1.3 .
-
- 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.
- // <<<<<<< TIGER SPECIFIC CHANGE >>>>>>>>>
- // As we are not supporting Xalan interpretive we are taking away the functionality
- // dependent on XSLT interpretive Transformer. Only way supported is to use XSLTC
- // and the execution path needed for supporting standard XPath API defined by
- // JAXP 1.3 .
-
- 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;
- }
-
-
- }