- /*
- * Copyright 2001-2004 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.
- */
- /*
- * $Id: VariableBase.java,v 1.23 2004/02/24 02:57:28 zongaro Exp $
- */
-
- package com.sun.org.apache.xalan.internal.xsltc.compiler;
-
- import java.util.Vector;
-
- import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
- import com.sun.org.apache.bcel.internal.generic.Instruction;
- import com.sun.org.apache.bcel.internal.generic.InstructionList;
- import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
- import com.sun.org.apache.bcel.internal.generic.LocalVariableGen;
- import com.sun.org.apache.bcel.internal.generic.NEW;
- import com.sun.org.apache.bcel.internal.generic.PUSH;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.NodeSetType;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
- import com.sun.org.apache.xml.internal.utils.XMLChar;
-
- /**
- * @author Jacek Ambroziak
- * @author Santiago Pericas-Geertsen
- * @author Morten Jorgensen
- * @author Erwin Bolwidt <ejb@klomp.org>
- * @author John Howard <JohnH@schemasoft.com>
- */
- class VariableBase extends TopLevelElement {
-
- protected QName _name; // The name of the variable.
- protected String _escapedName; // The escaped qname of the variable.
- protected Type _type; // The type of this variable.
- protected boolean _isLocal; // True if the variable is local.
- protected LocalVariableGen _local; // Reference to JVM variable
- protected Instruction _loadInstruction; // Instruction to load JVM variable
- protected Instruction _storeInstruction; // Instruction to load JVM variable
- protected Expression _select; // Reference to variable expression
- protected String select; // Textual repr. of variable expr.
-
- // References to this variable (when local)
- protected Vector _refs = new Vector(2);
-
- // Dependencies to other variables/parameters (for globals only)
- protected Vector _dependencies = null;
-
- // Used to make sure parameter field is not added twice
- protected boolean _ignore = false;
-
- // Used to order top-level variables so that there are no forward references
- protected int _weight = 0;
-
- /**
- * Disable this variable/parameter
- */
- public void disable() {
- _ignore = true;
- }
-
- /**
- * Add a reference to this variable. Called by VariableRef when an
- * expression contains a reference to this variable.
- */
- public void addReference(VariableRefBase vref) {
- _refs.addElement(vref);
- }
-
- /**
- * Remove a reference to this variable. Called by VariableRef when this
- * variable goes out of scope.
- */
- public void removeReference(VariableRefBase vref) {
- _refs.remove(vref);
- }
-
- /**
- *
- */
- public void addDependency(VariableBase other) {
- if (_dependencies == null) {
- _dependencies = new Vector();
- }
- if (!_dependencies.contains(other)) {
- _dependencies.addElement(other);
- }
- }
-
- /**
- *
- */
- public Vector getDependencies() {
- return _dependencies;
- }
-
- /**
- * Map this variable to a register
- */
- public void mapRegister(MethodGenerator methodGen) {
- if (_local == null) {
- final InstructionList il = methodGen.getInstructionList();
- final String name = getEscapedName(); // TODO: namespace ?
- final com.sun.org.apache.bcel.internal.generic.Type varType = _type.toJCType();
- _local = methodGen.addLocalVariable2(name, varType, il.getEnd());
- }
- }
-
- /**
- * Remove the mapping of this variable to a register.
- * Called when we leave the AST scope of the variable's declaration
- */
- public void unmapRegister(MethodGenerator methodGen) {
- if (_refs.isEmpty() && (_local != null)) {
- _local.setEnd(methodGen.getInstructionList().getEnd());
- methodGen.removeLocalVariable(_local);
- _refs = null;
- _local = null;
- }
- }
-
- /**
- * Returns an instruction for loading the value of this variable onto
- * the JVM stack.
- */
- public Instruction loadInstruction() {
- final Instruction instr = _loadInstruction;
- if (_loadInstruction == null) {
- _loadInstruction = _type.LOAD(_local.getIndex());
- }
- return _loadInstruction;
- }
-
- /**
- * Returns an instruction for storing a value from the JVM stack
- * into this variable.
- */
- public Instruction storeInstruction() {
- final Instruction instr = _storeInstruction;
- if (_storeInstruction == null) {
- _storeInstruction = _type.STORE(_local.getIndex());
- }
- return _storeInstruction;
- }
-
- /**
- * Returns the expression from this variable's select attribute (if any)
- */
- public Expression getExpression() {
- return(_select);
- }
-
- /**
- * Display variable as single string
- */
- public String toString() {
- return("variable("+_name+")");
- }
-
- /**
- * Display variable in a full AST dump
- */
- public void display(int indent) {
- indent(indent);
- System.out.println("Variable " + _name);
- if (_select != null) {
- indent(indent + IndentIncrement);
- System.out.println("select " + _select.toString());
- }
- displayContents(indent + IndentIncrement);
- }
-
- /**
- * Returns the type of the variable
- */
- public Type getType() {
- return _type;
- }
-
- /**
- * Returns the name of the variable or parameter as it will occur in the
- * compiled translet.
- */
- public QName getName() {
- return _name;
- }
-
- /**
- * Returns the escaped qname of the variable or parameter
- */
- public String getEscapedName() {
- return _escapedName;
- }
-
- /**
- * Set the name of the variable or paremeter. Escape all special chars.
- */
- public void setName(QName name) {
- _name = name;
- _escapedName = Util.escape(name.getStringRep());
- }
-
- /**
- * Returns the true if the variable is local
- */
- public boolean isLocal() {
- return _isLocal;
- }
-
- /**
- * Parse the contents of the <xsl:decimal-format> element.
- */
- public void parseContents(Parser parser) {
- // Get the 'name attribute
- String name = getAttribute("name");
-
- if (name.length() > 0) {
- if (!XMLChar.isValidQName(name)) {
- ErrorMsg err = new ErrorMsg(ErrorMsg.INVALID_QNAME_ERR, name, this);
- parser.reportError(Constants.ERROR, err);
- }
- setName(parser.getQNameIgnoreDefaultNs(name));
- }
- else
- reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "name");
-
- // Check whether variable/param of the same name is already in scope
- VariableBase other = parser.lookupVariable(_name);
- if ((other != null) && (other.getParent() == getParent())) {
- reportError(this, parser, ErrorMsg.VARIABLE_REDEF_ERR, name);
- }
-
- select = getAttribute("select");
- if (select.length() > 0) {
- _select = getParser().parseExpression(this, "select", null);
- if (_select.isDummy()) {
- reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "select");
- return;
- }
- }
-
- // Children must be parsed first -> static scoping
- parseChildren(parser);
- }
-
- /**
- * Compile the value of the variable, which is either in an expression in
- * a 'select' attribute, or in the variable elements body
- */
- public void translateValue(ClassGenerator classGen,
- MethodGenerator methodGen) {
- // Compile expression is 'select' attribute if present
- if (_select != null) {
- _select.translate(classGen, methodGen);
- // Create a CachedNodeListIterator for select expressions
- // in a variable or parameter.
- if (_select.getType() instanceof NodeSetType) {
- final ConstantPoolGen cpg = classGen.getConstantPool();
- final InstructionList il = methodGen.getInstructionList();
-
- final int initCNI = cpg.addMethodref(CACHED_NODE_LIST_ITERATOR_CLASS,
- "<init>",
- "("
- +NODE_ITERATOR_SIG
- +")V");
- il.append(new NEW(cpg.addClass(CACHED_NODE_LIST_ITERATOR_CLASS)));
- il.append(DUP_X1);
- il.append(SWAP);
-
- il.append(new INVOKESPECIAL(initCNI));
- }
- _select.startIterator(classGen, methodGen);
- }
- // If not, compile result tree from parameter body if present.
- else if (hasContents()) {
- compileResultTree(classGen, methodGen);
- }
- // If neither are present then store empty string in variable
- else {
- final ConstantPoolGen cpg = classGen.getConstantPool();
- final InstructionList il = methodGen.getInstructionList();
- il.append(new PUSH(cpg, Constants.EMPTYSTRING));
- }
- }
-
- }