| /* |
| * 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: XUnresolvedVariable.java 468643 2006-10-28 06:56:03Z minchau $ |
| */ |
| package org.apache.xalan.templates; |
| |
| import org.apache.xalan.res.XSLTErrorResources; |
| import org.apache.xalan.transformer.TransformerImpl; |
| import org.apache.xpath.VariableStack; |
| import org.apache.xpath.XPathContext; |
| import org.apache.xpath.objects.XObject; |
| |
| /** |
| * An instance of this class holds unto a variable until |
| * it is executed. It is used at this time for global |
| * variables which must (we think) forward reference. |
| */ |
| public class XUnresolvedVariable extends XObject |
| { |
| static final long serialVersionUID = -256779804767950188L; |
| /** The node context for execution. */ |
| transient private int m_context; |
| |
| /** The transformer context for execution. */ |
| transient private TransformerImpl m_transformer; |
| |
| /** An index to the point in the variable stack where we should |
| * begin variable searches for evaluation of expressions. |
| * This is -1 if m_isTopLevel is false. |
| **/ |
| transient private int m_varStackPos = -1; |
| |
| /** An index into the variable stack where the variable context |
| * ends, i.e. at the point we should terminate the search. |
| **/ |
| transient private int m_varStackContext; |
| |
| /** true if this variable or parameter is a global. |
| * @serial */ |
| private boolean m_isGlobal; |
| |
| /** true if this variable or parameter is not currently being evaluated. */ |
| transient private boolean m_doneEval = true; |
| |
| /** |
| * Create an XUnresolvedVariable, that may be executed at a later time. |
| * This is primarily used so that forward referencing works with |
| * global variables. An XUnresolvedVariable is initially pushed |
| * into the global variable stack, and then replaced with the real |
| * thing when it is accessed. |
| * |
| * @param obj Must be a non-null reference to an ElemVariable. |
| * @param sourceNode The node context for execution. |
| * @param transformer The transformer execution context. |
| * @param varStackPos An index to the point in the variable stack where we should |
| * begin variable searches for evaluation of expressions. |
| * @param varStackContext An index into the variable stack where the variable context |
| * ends, i.e. at the point we should terminate the search. |
| * @param isGlobal true if this is a global variable. |
| */ |
| public XUnresolvedVariable(ElemVariable obj, int sourceNode, |
| TransformerImpl transformer, |
| int varStackPos, int varStackContext, |
| boolean isGlobal) |
| { |
| super(obj); |
| m_context = sourceNode; |
| m_transformer = transformer; |
| |
| // For globals, this value will have to be updated once we |
| // have determined how many global variables have been pushed. |
| m_varStackPos = varStackPos; |
| |
| // For globals, this should zero. |
| m_varStackContext = varStackContext; |
| |
| m_isGlobal = isGlobal; |
| } |
| |
| /** |
| * For support of literal objects in xpaths. |
| * |
| * @param xctxt The XPath execution context. |
| * |
| * @return This object. |
| * |
| * @throws javax.xml.transform.TransformerException |
| */ |
| public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException |
| { |
| if (!m_doneEval) |
| { |
| this.m_transformer.getMsgMgr().error |
| (xctxt.getSAXLocator(), XSLTErrorResources.ER_REFERENCING_ITSELF, |
| new Object[]{((ElemVariable)this.object()).getName().getLocalName()}); |
| } |
| VariableStack vars = xctxt.getVarStack(); |
| |
| // These three statements need to be combined into one operation. |
| int currentFrame = vars.getStackFrame(); |
| //// vars.setStackFrame(m_varStackPos); |
| |
| |
| ElemVariable velem = (ElemVariable)m_obj; |
| try |
| { |
| m_doneEval = false; |
| if(-1 != velem.m_frameSize) |
| vars.link(velem.m_frameSize); |
| XObject var = velem.getValue(m_transformer, m_context); |
| m_doneEval = true; |
| return var; |
| } |
| finally |
| { |
| // These two statements need to be combined into one operation. |
| // vars.setStackFrame(currentFrame); |
| |
| if(-1 != velem.m_frameSize) |
| vars.unlink(currentFrame); |
| } |
| } |
| |
| /** |
| * Set an index to the point in the variable stack where we should |
| * begin variable searches for evaluation of expressions. |
| * This is -1 if m_isTopLevel is false. |
| * |
| * @param top A valid value that specifies where in the variable |
| * stack the search should begin. |
| */ |
| public void setVarStackPos(int top) |
| { |
| m_varStackPos = top; |
| } |
| |
| /** |
| * Set an index into the variable stack where the variable context |
| * ends, i.e. at the point we should terminate the search. |
| * |
| * @param bottom The point at which the search should terminate, normally |
| * zero for global variables. |
| */ |
| public void setVarStackContext(int bottom) |
| { |
| m_varStackContext = bottom; |
| } |
| |
| /** |
| * Tell what kind of class this is. |
| * |
| * @return CLASS_UNRESOLVEDVARIABLE |
| */ |
| public int getType() |
| { |
| return CLASS_UNRESOLVEDVARIABLE; |
| } |
| |
| /** |
| * Given a request type, return the equivalent string. |
| * For diagnostic purposes. |
| * |
| * @return An informational string. |
| */ |
| public String getTypeString() |
| { |
| return "XUnresolvedVariable (" + object().getClass().getName() + ")"; |
| } |
| |
| |
| } |