/*****************************************************************************
 *                                                                           *
 *  This file is part of the BeanShell Java Scripting distribution.          *
 *  Documentation and updates may be found at http://www.beanshell.org/      *
 *                                                                           *
 *  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.                                          *
 *                                                                           *
 *  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 *
 *  allow use of your version of this file only under the  terms of the LGPL *
 *  and not to allow others to use your version of this file under the SPL,  *
 *  indicate your decision by deleting the provisions above and replace      *
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 *  do not delete the provisions above, a recipient may use your version of  *
 *  this file under either the SPL or the LGPL.                              *
 *                                                                           *
 *  Patrick Niemeyer (pat@pat.net)                                           *
 *  Author of Learning Java, O'Reilly & Associates                           *
 *  http://www.pat.net/~pat/                                                 *
 *                                                                           *
 *****************************************************************************/


package bsh;

/**
	UtilEvalError is an error corresponding to an EvalError but thrown by a 
	utility or other class that does not have the caller context (Node) 
	available to it.  A normal EvalError must supply the caller Node in order 
	for error messages to be pinned to the correct line and location in the 
	script.  UtilEvalError is a checked exception that is *not* a subtype of 
	EvalError, but instead must be caught and rethrown as an EvalError by 
	the a nearest location with context.  The method toEvalError( Node ) 
	should be used to throw the EvalError, supplying the node.
	


	To summarize: Utilities throw UtilEvalError.  ASTs throw EvalError.
	ASTs catch UtilEvalError and rethrow it as EvalError using 
	toEvalError( Node ).  
	


	Philosophically, EvalError and UtilEvalError corrospond to 
	RuntimeException.  However they are constrained in this way in order to 
	add the context for error reporting.

	@see UtilTargetError
*/
public class UtilEvalError extends Exception 
{
	protected UtilEvalError() {
	}

	public UtilEvalError( String s ) {
		super(s);
	}

	/**
		Re-throw as an eval error, prefixing msg to the message and specifying
		the node.  If a node already exists the addNode is ignored.
		@see #setNode( bsh.SimpleNode )
		

		@param msg may be null for no additional message.
	*/
	public EvalError toEvalError( 
		String msg, SimpleNode node, CallStack callstack  ) 
	{
		if ( Interpreter.DEBUG )
			printStackTrace();

		if ( msg == null )
			msg = "";
		else
			msg = msg + ": ";
		return new EvalError( msg+getMessage(), node, callstack );
	}

	public EvalError toEvalError ( SimpleNode node, CallStack callstack ) 
	{
		return toEvalError( null, node, callstack );
	}

}