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/*****************************************************************************
 *                                                                           *
 *  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      *
 *  them with the notice and other provisions required by the LGPL.  If you  *
 *  do not delete the provisions above, a recipient may use your version of  *
 *  this file under either the SPL or the LGPL.                              *
 *                                                                           *
 *  Patrick Niemeyer ([email protected])                                           *
 *  Author of Learning Java, O'Reilly & Associates                           *
 *  http://www.pat.net/~pat/                                                 *
 *                                                                           *
 *****************************************************************************/

package	bsh;

import java.util.Vector;

/**
	A ClassNameSpace represents the body a scripted class definition or
	scripted class instance.  In the case of the class definition it serves as
	the Class object and holds the class initializer method (called before the
	constructor).
	
	When serving as a class definition, only static members are visible and
	attempting to access an instance member will cause a "can't reach instance
	from static context" exception.
	

	When serving as a class instance static members are dissallowed (except
	by the initializer) and are ignored, allowing them to be seen in the class
	definition.
	

	Class instances also serve as the top scope of instance variables declared
	within the class (by the initializer).
*/
/*
	This would obviously be cleaner if we made a second subclass of NameSpace:
	ClassInstanceNameSpace.
*/
public class ClassNameSpace extends NameSpace 
{
	/** Java class for this class static body */
	Class javaClass;

	/** Java instance object for this class instance */
	Object javaObject;

    public ClassNameSpace( 
		NameSpace parent, String name, Class javaClass ) 
		throws EvalError
	{
		super( parent, name );
		this.javaClass = javaClass;
    }

	/**
		Instance constructor
	*/
    public ClassNameSpace( ClassNameSpace parent, Object javaObject ) 
		throws EvalError
	{
		super( parent, parent.getName() );
		this.javaObject = javaObject;
    }

	public This constructClassInstance( Object[] args, 
		Interpreter interpreter, CallStack callstack, SimpleNode callerInfo ) 
		throws EvalError
	{
		ClassNameSpace classNameSpace = this;
		String className = classNameSpace.getName();

		BshMethod classInitializer = null;
		try {
			classInitializer = 
				classNameSpace.getMethod( 
					BSHClassDeclaration.CLASSINITNAME, new Class[0] );
		} catch ( UtilEvalError e ) { // shouldn't happen
			throw e.toEvalError(
				"Error getting class initializer", callerInfo, callstack );
		}
		if ( classInitializer == null )
			throw new EvalError("Unable to find initializer for class.",
				callerInfo, callstack);

		// Get the (non-initializer) constructor, if any
		Class [] sig = Types.getTypes( args );
		BshMethod constructor = null;
		try {
			constructor = 
				classNameSpace.getMethod( className, sig );
		} catch ( UtilEvalError e ) { // shouldn't happen
			throw e.toEvalError(
				"Error getting constructor", callerInfo, callstack );
		}
		// No constructor found
		if ( constructor == null )
		{
			// args constructor not found
			if ( args.length > 0 )
				throw new EvalError("Constructor not found: "+
					StringUtil.methodString( className, sig ),
					callerInfo, callstack );
			else
			// no args constructor missing. Ok if no other constructors exist
			{
				BshMethod [] methods = classNameSpace.getMethods();
				for(int i=0; i