/*
* $Workfile: HelloWorld.java $	$Revision: 1 $, $Date: 2/10/98 3:43p $
*
* Copyright (c) 1997 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the confidential and proprietary information of Sun
* Microsystems, Inc. ("Confidential Information").  You shall not
* disclose such Confidential Information and shall use it only in
* accordance with the terms of the license agreement you entered into
* with Sun.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
* SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
* IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
* SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
* THIS SOFTWARE OR ITS DERIVATIVES.
*/

// /*
// $Workfile: HelloWorld.java $
// $Revision: 1 $
// $Date: 2/10/98 3:43p $
// $Author: Vadim $
// $Archive: /Releases/L 980212 JC20-DR2-P/Input/Sample-Code/src/HelloWorld/HelloWorld.java $
// $Modtime: 12/19/97 2:54p $
// Original author:  Mitch Butler
// */

package applets.HelloWorld;

import javacard.framework.*;

/**
 */

public class HelloWorld extends Applet
{
    private byte[] echoBytes;
    private static final short LENGTH_ECHO_BYTES = 256;
    
    /**
     * Only this class's install method should create the applet object.
     * @see APDU
     * @param apdu the incoming APDU containing the INSTALL command.
     */
    protected HelloWorld(APDU apdu)
    {
        register();
        echoBytes = new byte[LENGTH_ECHO_BYTES];
    }

    /**
     * Installs this applet.
     * @see APDU
     * @param apdu the incoming APDU containing the INSTALL command.
     * @exception ISOException with the response bytes per ISO 7816-4
     */
    public static void install(APDU apdu)
    {
        new HelloWorld(apdu);
    }

    /**
     * Processes an incoming APDU.
     * @see APDU
     * @param apdu the incoming APDU
     * @exception ISOException with the response bytes per ISO 7816-4
     */
    public void process(APDU apdu)
    {
        byte buffer[] = apdu.getBuffer();

		short bytesRead = apdu.setIncomingAndReceive();
		short echoOffset = (short)0;

		while ( bytesRead > 0 ) {
            Util.arrayCopyNonAtomic(buffer, ISO.OFFSET_CDATA, echoBytes, echoOffset, bytesRead);
            echoOffset += bytesRead;
            bytesRead = apdu.receiveBytes(ISO.OFFSET_CDATA);
        }
        
        apdu.setOutgoing();
        apdu.setOutgoingLength( (short) (echoOffset + 5) );
        
        // echo header
        apdu.sendBytes( (short)0, (short) 5);
        // echo data
        apdu.sendBytesLong( echoBytes, (short) 0, echoOffset );
    }

}