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: CastCall.java,v 1.2.4.1 2005/09/01 11:47:58 pvedula Exp $
22  */
23 
24 package com.sun.org.apache.xalan.internal.xsltc.compiler;
25 
26 import java.util.Vector;
27 
28 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
29 import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
30 import com.sun.org.apache.bcel.internal.generic.InstructionList;
31 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
32 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
33 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
34 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
35 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ObjectType;
36 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
37 
38 /**
39  * @author Santiago Pericas-Geertsen
40  */
41 final class CastCall extends FunctionCall {
42 
43     /**
44      * Name of the class that is the target of the cast. Must be a
45      * fully-qualified Java class Name.
46      */
47     private String _className;
48 
49     /**
50      * A reference to the expression being casted.
51      */
52     private Expression _right;
53 
54     /**
55      * Constructor.
56      */
CastCall(QName fname, Vector arguments)57     public CastCall(QName fname, Vector arguments) {
58         super(fname, arguments);
59     }
60 
61     /**
62      * Type check the two parameters for this function
63      */
typeCheck(SymbolTable stable)64     public Type typeCheck(SymbolTable stable) throws TypeCheckError {
65         // Check that the function was passed exactly two arguments
66         if (argumentCount() != 2) {
67             throw new TypeCheckError(new ErrorMsg(ErrorMsg.ILLEGAL_ARG_ERR,
68                                                   getName(), this));
69         }
70 
71         // The first argument must be a literal String
72         Expression exp = argument(0);
73         if (exp instanceof LiteralExpr) {
74             _className = ((LiteralExpr) exp).getValue();
75             _type = Type.newObjectType(_className);
76         }
77         else {
78             throw new TypeCheckError(new ErrorMsg(ErrorMsg.NEED_LITERAL_ERR,
79                                                   getName(), this));
80         }
81 
82          // Second argument must be of type reference or object
83         _right = argument(1);
84         Type tright = _right.typeCheck(stable);
85         if (tright != Type.Reference &&
86             tright instanceof ObjectType == false)
87         {
88             throw new TypeCheckError(new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
89                                                   tright, _type, this));
90         }
91 
92         return _type;
93     }
94 
translate(ClassGenerator classGen, MethodGenerator methodGen)95     public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
96         final ConstantPoolGen cpg = classGen.getConstantPool();
97         final InstructionList il = methodGen.getInstructionList();
98 
99         _right.translate(classGen, methodGen);
100         il.append(new CHECKCAST(cpg.addClass(_className)));
101     }
102 }
103