| /* |
| * 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. |
| */ |
| /* |
| * $Id$ |
| */ |
| |
| package org.apache.xalan.xsltc.compiler; |
| |
| import org.apache.bcel.generic.ALOAD; |
| import org.apache.bcel.generic.ASTORE; |
| import org.apache.bcel.generic.ConstantPoolGen; |
| import org.apache.bcel.generic.INVOKEINTERFACE; |
| import org.apache.bcel.generic.INVOKESPECIAL; |
| import org.apache.bcel.generic.InstructionList; |
| import org.apache.bcel.generic.LocalVariableGen; |
| import org.apache.bcel.generic.NEW; |
| import org.apache.xalan.xsltc.compiler.util.ClassGenerator; |
| import org.apache.xalan.xsltc.compiler.util.MethodGenerator; |
| import org.apache.xalan.xsltc.compiler.util.NodeType; |
| import org.apache.xalan.xsltc.compiler.util.Type; |
| import org.apache.xalan.xsltc.compiler.util.TypeCheckError; |
| import org.apache.xalan.xsltc.compiler.util.Util; |
| |
| /** |
| * @author G. Todd Miller |
| */ |
| final class FilteredAbsoluteLocationPath extends Expression { |
| private Expression _path; // may be null |
| |
| public FilteredAbsoluteLocationPath() { |
| _path = null; |
| } |
| |
| public FilteredAbsoluteLocationPath(Expression path) { |
| _path = path; |
| if (path != null) { |
| _path.setParent(this); |
| } |
| } |
| |
| public void setParser(Parser parser) { |
| super.setParser(parser); |
| if (_path != null) { |
| _path.setParser(parser); |
| } |
| } |
| |
| public Expression getPath() { |
| return(_path); |
| } |
| |
| public String toString() { |
| return "FilteredAbsoluteLocationPath(" + |
| (_path != null ? _path.toString() : "null") + ')'; |
| } |
| |
| public Type typeCheck(SymbolTable stable) throws TypeCheckError { |
| if (_path != null) { |
| final Type ptype = _path.typeCheck(stable); |
| if (ptype instanceof NodeType) { // promote to node-set |
| _path = new CastExpr(_path, Type.NodeSet); |
| } |
| } |
| return _type = Type.NodeSet; |
| } |
| |
| public void translate(ClassGenerator classGen, MethodGenerator methodGen) { |
| final ConstantPoolGen cpg = classGen.getConstantPool(); |
| final InstructionList il = methodGen.getInstructionList(); |
| if (_path != null) { |
| final int initDFI = cpg.addMethodref(DUP_FILTERED_ITERATOR, |
| "<init>", |
| "(" |
| + NODE_ITERATOR_SIG |
| + ")V"); |
| |
| // Backwards branches are prohibited if an uninitialized object is |
| // on the stack by section 4.9.4 of the JVM Specification, 2nd Ed. |
| // We don't know whether this code might contain backwards branches, |
| // so we mustn't create the new object until after we've created |
| // the suspect arguments to its constructor. Instead we calculate |
| // the values of the arguments to the constructor first, store them |
| // in temporary variables, create the object and reload the |
| // arguments from the temporaries to avoid the problem. |
| |
| // Compile relative path iterator(s) |
| LocalVariableGen pathTemp = |
| methodGen.addLocalVariable("filtered_absolute_location_path_tmp", |
| Util.getJCRefType(NODE_ITERATOR_SIG), |
| null, null); |
| _path.translate(classGen, methodGen); |
| pathTemp.setStart(il.append(new ASTORE(pathTemp.getIndex()))); |
| |
| // Create new Dup Filter Iterator |
| il.append(new NEW(cpg.addClass(DUP_FILTERED_ITERATOR))); |
| il.append(DUP); |
| pathTemp.setEnd(il.append(new ALOAD(pathTemp.getIndex()))); |
| |
| // Initialize Dup Filter Iterator with iterator from the stack |
| il.append(new INVOKESPECIAL(initDFI)); |
| } |
| else { |
| final int git = cpg.addInterfaceMethodref(DOM_INTF, |
| "getIterator", |
| "()"+NODE_ITERATOR_SIG); |
| il.append(methodGen.loadDOM()); |
| il.append(new INVOKEINTERFACE(git, 1)); |
| } |
| } |
| } |