- /*
- * 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: If.java,v 1.13 2004/02/16 22:24:29 minchau Exp $
- */
-
- package com.sun.org.apache.xalan.internal.xsltc.compiler;
-
- import com.sun.org.apache.bcel.internal.generic.InstructionHandle;
- import com.sun.org.apache.bcel.internal.generic.InstructionList;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.BooleanType;
- 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.Type;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
- import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
-
- /**
- * @author Jacek Ambroziak
- * @author Santiago Pericas-Geertsen
- * @author Morten Jorgensen
- */
- final class If extends Instruction {
-
- private Expression _test;
- private boolean _ignore = false;
-
- /**
- * Display the contents of this element
- */
- public void display(int indent) {
- indent(indent);
- Util.println("If");
- indent(indent + IndentIncrement);
- System.out.print("test ");
- Util.println(_test.toString());
- displayContents(indent + IndentIncrement);
- }
-
- /**
- * Parse the "test" expression and contents of this element.
- */
- public void parseContents(Parser parser) {
- // Parse the "test" expression
- _test = parser.parseExpression(this, "test", null);
-
- // Make sure required attribute(s) have been set
- if (_test.isDummy()) {
- reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "test");
- return;
- }
-
- // Ignore xsl:if when test is false (function-available() and
- // element-available())
- Object result = _test.evaluateAtCompileTime();
- if (result != null && result instanceof Boolean) {
- _ignore = !((Boolean) result).booleanValue();
- }
-
- parseChildren(parser);
- }
-
- /**
- * Type-check the "test" expression and contents of this element.
- * The contents will be ignored if we know the test will always fail.
- */
- public Type typeCheck(SymbolTable stable) throws TypeCheckError {
- // Type-check the "test" expression
- if (_test.typeCheck(stable) instanceof BooleanType == false) {
- _test = new CastExpr(_test, Type.Boolean);
- }
- // Type check the element contents
- if (!_ignore) {
- typeCheckContents(stable);
- }
- return Type.Void;
- }
-
- /**
- * Translate the "test" expression and contents of this element.
- * The contents will be ignored if we know the test will always fail.
- */
- public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
- final InstructionList il = methodGen.getInstructionList();
- _test.translateDesynthesized(classGen, methodGen);
- // remember end of condition
- final InstructionHandle truec = il.getEnd();
- if (!_ignore) {
- translateContents(classGen, methodGen);
- }
- _test.backPatchFalseList(il.append(NOP));
- _test.backPatchTrueList(truec.getNext());
- }
- }