1 /*
   2  * reserved comment block
   3  * DO NOT REMOVE OR ALTER!
   4  */
   5 /*
   6  * Copyright 2001-2004 The Apache Software Foundation.
   7  *
   8  * Licensed under the Apache License, Version 2.0 (the "License");
   9  * you may not use this file except in compliance with the License.
  10  * You may obtain a copy of the License at
  11  *
  12  *     http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20 /*
  21  * $Id: Comment.java,v 1.2.4.1 2005/09/01 12:02:37 pvedula Exp $
  22  */
  23 
  24 package com.sun.org.apache.xalan.internal.xsltc.compiler;
  25 
  26 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  27 import com.sun.org.apache.bcel.internal.generic.GETFIELD;
  28 import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
  29 import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
  30 import com.sun.org.apache.bcel.internal.generic.PUSH;
  31 import com.sun.org.apache.bcel.internal.generic.InstructionList;
  32 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
  33 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
  34 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
  35 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
  36 
  37 /**
  38  * @author Jacek Ambroziak
  39  * @author Santiago Pericas-Geertsen
  40  * @author Morten Jorgensen
  41  */
  42 final class Comment extends Instruction {
  43 
  44     public void parseContents(Parser parser) {
  45         parseChildren(parser);
  46     }
  47 
  48     public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  49         typeCheckContents(stable);
  50         return Type.String;
  51     }
  52 
  53     public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
  54         final ConstantPoolGen cpg = classGen.getConstantPool();
  55         final InstructionList il = methodGen.getInstructionList();
  56 
  57         // Shortcut for literal strings
  58         Text rawText = null;
  59         if (elementCount() == 1) {
  60             Object content = elementAt(0);
  61             if (content instanceof Text) {
  62                 rawText = (Text) content;
  63             }
  64         }
  65 
  66         // If the content is literal text, call comment(char[],int,int) or
  67         // comment(String), as appropriate.  Otherwise, use a
  68         // StringValueHandler to gather the textual content of the xsl:comment
  69         // and call comment(String) with the result.
  70         if (rawText != null) {
  71             il.append(methodGen.loadHandler());
  72 
  73             if (rawText.canLoadAsArrayOffsetLength()) {
  74                 rawText.loadAsArrayOffsetLength(classGen, methodGen);
  75                 final int comment =
  76                         cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
  77                                                   "comment",
  78                                                   "([CII)V");
  79                 il.append(new INVOKEINTERFACE(comment, 4));
  80             } else {
  81                 il.append(new PUSH(cpg, rawText.getText()));
  82                 final int comment =
  83                         cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
  84                                                   "comment",
  85                                                   "(" + STRING_SIG + ")V");
  86                 il.append(new INVOKEINTERFACE(comment, 2));
  87             }
  88         } else {
  89             // Save the current handler base on the stack
  90             il.append(methodGen.loadHandler());
  91             il.append(DUP);             // first arg to "comment" call
  92 
  93             // Get the translet's StringValueHandler
  94             il.append(classGen.loadTranslet());
  95             il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
  96                                                    "stringValueHandler",
  97                                                    STRING_VALUE_HANDLER_SIG)));
  98             il.append(DUP);
  99             il.append(methodGen.storeHandler());
 100 
 101             // translate contents with substituted handler
 102             translateContents(classGen, methodGen);
 103 
 104             // get String out of the handler
 105             il.append(new INVOKEVIRTUAL(cpg.addMethodref(STRING_VALUE_HANDLER,
 106                                                          "getValue",
 107                                                          "()" + STRING_SIG)));
 108             // call "comment"
 109             final int comment =
 110                         cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
 111                                                   "comment",
 112                                                   "(" + STRING_SIG + ")V");
 113             il.append(new INVOKEINTERFACE(comment, 2));
 114             // Restore old handler base from stack
 115             il.append(methodGen.storeHandler());
 116         }
 117     }
 118 }