encarrayencoder.java

Java Communicating Agents是一个用于开发网络反应式信息agent的框架

/*
 * $Source: /home/data/cvsroot/src/jacomma/icm/io/imp/EncArrayEncoder.java,v $
 * $Revision: 1.7 $
 * $Date: 2000/10/28 20:09:07 $
 *
 * This file is part of the jacomma framework
 * Copyright (c) 2000 	Dimitrios Vyzovitis
 *			mailto:[e-mail]
 *			
 *
 *			
 *			
 *			
 *
 *	This library is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU Library General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This library is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *	GNU Library General Public License for more details.
 *
 *	You should have received a copy of the GNU Library General Public License
 *	along with this library; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, 
 *	Boston, MA  02111-1307  USA
 */

package jacomma.icm.io.imp;

import jacomma.icm.io.EncObject;
import jacomma.icm.io.EncObjectType;
import jacomma.icm.io.ObjectEncoder;
import jacomma.icm.io.EncObjectSignature;

/**
 * TBA
 **/
public class EncArrayEncoder extends EncoderTemplate {

	public EncArrayEncoder() {
		all_.add( java.lang.reflect.Array
				  .newInstance( EncObject.class, 0 ).getClass() ); 
	}
	
	public EncObject encode( Object obj, Object hint, boolean s ) {
		// check signatures
		// if all identical, encode as a list
		// if they differ, encode as a tuple
		// the hint can specify whether the array should be encoded as a Tuple
		// or a List and thus override the signature determination algorithm
		CacheKey key = new CacheKey( obj, hint );
		EncObject eo = null;
		
		if ( (eo = (EncObject)cache_.get( key )) == null ) {
			EncObjectType t = (hint instanceof EncObjectType) ? (EncObjectType)hint : null;
			if ( t == null
				 || !(t.equals( EncObjectType.List ) 
					  || t.equals( EncObjectType.Tuple )) ) {
				
				EncObject[] array = (EncObject[])obj;
				t = EncObjectType.List;
				
				if ( array.length > 0 ) {
					String ts = EncObjectSignature.signatureOf( array[0] ); 
					for ( int i = 1;  i < array.length; i++ )
						if ( !ts.equals( EncObjectSignature.signatureOf( array[i] ) ) ) {
							t = EncObjectType.Tuple;
							break;
						}
				}
						 
			}
			
			eo = (EncObject)cache_.try_put( key, new EncObjectImp( t, obj ) );
		}
		
		return s ? sign( eo ) : eo;
	}

}