code: /*
   * 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 java.util.Vector;
  
  import org.apache.bcel.generic.ConstantPoolGen;
  import org.apache.bcel.generic.CHECKCAST;
  import org.apache.bcel.generic.InstructionList;
  import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
  import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
  import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
  import org.apache.xalan.xsltc.compiler.util.Type;
  import org.apache.xalan.xsltc.compiler.util.ObjectType;
  import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
  
  /**
   * @author Santiago Pericas-Geertsen
   */
  final class CastCall extends FunctionCall {
      
      /**
       * Name of the class that is the target of the cast. Must be a 
       * fully-qualified Java class Name.
       */
      private String _className;
  
      /**
       * A reference to the expression being casted.
       */
      private Expression _right;
  
      /**
       * Constructor.
       */
      public CastCall(QName fname, Vector arguments) {
  	super(fname, arguments);
      }
  
      /**
       * Type check the two parameters for this function
       */
      public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  	// Check that the function was passed exactly two arguments
  	if (argumentCount() != 2) {
  	    throw new TypeCheckError(new ErrorMsg(ErrorMsg.ILLEGAL_ARG_ERR,
                                                    getName(), this));
  	}
  
          // The first argument must be a literal String
  	Expression exp = argument(0);
          if (exp instanceof LiteralExpr) {
              _className = ((LiteralExpr) exp).getValue();
              _type = Type.newObjectType(_className);
          }
          else {
  	    throw new TypeCheckError(new ErrorMsg(ErrorMsg.NEED_LITERAL_ERR,
                                                    getName(), this));
          }
          
           // Second argument must be of type reference or object
          _right = argument(1);
          Type tright = _right.typeCheck(stable);
          if (tright != Type.Reference && 
              tright instanceof ObjectType == false) 
          {
  	    throw new TypeCheckError(new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
                                                    tright, _type, this));
          }
          
          return _type;
      }
      
      public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
  	final ConstantPoolGen cpg = classGen.getConstantPool();
  	final InstructionList il = methodGen.getInstructionList();
  
          _right.translate(classGen, methodGen);
          il.append(new CHECKCAST(cpg.addClass(_className)));
      }
  }
  