arrayreader.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/ArrayReader.java,v $
 * $Revision: 1.4 $
 * $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.EncObjectReader;


public abstract class ArrayReader extends ReaderTemplate {

	int sig_;
	EncObject[] elements_;

	int index_;
	EncObjectReader anyrd_;
	
	
	public ArrayReader(){}

	public void start( java.io.InputStream stream ) 
		throws java.io.IOException {
		
		super.start( stream );
		
		index_ = -1;
		
	}

	public void readNext() throws java.io.IOException {
		if ( index_ == -1 ) {
			elements_ = new EncObject[decodeSignature( (sig_ = readNextByte()) )];
			anyrd_ = Registry.instance.getReader( EncObjectType.Any );
		} else if ( index_ < elements_.length ) {
			for( anyrd_.start( stream_ ); anyrd_.hasNext(); anyrd_.readNext() );
			elements_[index_] = anyrd_.getObject();
		} else return;
		
		// elements_ is initialized at first pass
		done_ = (++index_ == elements_.length);
	}
	
	protected abstract int decodeSignature( int sig ) throws java.io.IOException;
		
	protected EncObject makeObject() {
		return new EncObjectImp( EncObjectType.typeOf( sig_ ), elements_ );
	}
	
}