/*****************************************************************************
 *                                                                           *
 *  This file is part of the BeanShell Java Scripting distribution.          *
 *  Documentation and updates may be found at http://www.beanshell.org/      *
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 *  Sun Public License Notice:                                               *
 *                                                                           *
 *  The contents of this file are subject to the Sun Public License Version  *
 *  1.0 (the "License"); you may not use this file except in compliance with *
 *  the License. A copy of the License is available at http://www.sun.com    * 
 *                                                                           *
 *  The Original Code is BeanShell. The Initial Developer of the Original    *
 *  Code is Pat Niemeyer. Portions created by Pat Niemeyer are Copyright     *
 *  (C) 2000.  All Rights Reserved.                                          *
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 *  GNU Public License Notice:                                               *
 *                                                                           *
 *  Alternatively, the contents of this file may be used under the terms of  *
 *  the GNU Lesser General Public License (the "LGPL"), in which case the    *
 *  provisions of LGPL are applicable instead of those above. If you wish to *
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 *                                                                           *
 *  Patrick Niemeyer (pat@pat.net)                                           *
 *  Author of Learning Java, O'Reilly & Associates                           *
 *  http://www.pat.net/~pat/                                                 *
 *                                                                           *
 *****************************************************************************/


package bsh;

/**
	Implement casts.

	I think it should be possible to simplify some of the code here by
	using the Types.getAssignableForm() method, but I haven't looked 
	into it.
*/
class BSHCastExpression extends SimpleNode {

    public BSHCastExpression(int id) { super(id); }

	/**
		@return the result of the cast.
	*/
	public Object eval(
		CallStack callstack, Interpreter interpreter ) throws EvalError
    {
		NameSpace namespace = callstack.top();
        Class toType = ((BSHType)jjtGetChild(0)).getType( 
			callstack, interpreter );
		SimpleNode expression = (SimpleNode)jjtGetChild(1);

        // evaluate the expression
        Object fromValue = expression.eval(callstack, interpreter);
        Class fromType = fromValue.getClass();

		// TODO: need to add isJavaCastable() test for strictJava
		// (as opposed to isJavaAssignable())
		try {
			return Types.castObject( fromValue, toType, Types.CAST );
		} catch ( UtilEvalError e ) {
			throw e.toEvalError( this, callstack  );
		}
    }

}
