Java Card Example - Loopy

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package testjcard;

import javacard.framework.APDU;
import javacard.framework.Applet;
import javacard.framework.ISO7816;
import javacard.framework.ISOException;
import javacard.framework.Util;

/**
 *
 * @author colin
 */
public class JCardTest extends Applet {
    private byte[] echoBytes;
    private static final short LENGTH_ECHO_BYTES = 32;

    /**
     * Installs this applet.
     *
     * @param bArray
     *            the array containing installation parameters
     * @param bOffset
     *            the starting offset in bArray
     * @param bLength
     *            the length in bytes of the parameter data in bArray
     */
    public static void install(byte[] bArray, short bOffset, byte bLength) {
        new JCardTest();
    }

    /**
     * Only this class's install method should create the applet object.
     */
    protected JCardTest() {
        echoBytes = new byte[LENGTH_ECHO_BYTES];
        register();
    }




    /**
     * Processes an incoming APDU.
     *
     * @see APDU
     * @param apdu
     *            the incoming APDU
     */
    public void process(APDU apdu) {
         byte buffer[] = apdu.getBuffer();

        // check SELECT APDU command
        if ((buffer[ISO7816.OFFSET_CLA] == 0) &&
                (buffer[ISO7816.OFFSET_INS] == (byte) (0xA4))) {
            return;
        }

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

        short outerLoopCounter = 0;
        short innerLoopCounter = 0;
        short iterations = (short) 0;


        while (bytesRead > 0) {
            //Util.arrayCopyNonAtomic(buffer, ISO7816.OFFSET_CDATA, echoBytes, echoOffset, bytesRead);
            //echoOffset += bytesRead;
            bytesRead = apdu.receiveBytes(ISO7816.OFFSET_CDATA);
        }

        for(outerLoopCounter=0;outerLoopCounter<2;outerLoopCounter++){
            for(innerLoopCounter=0;innerLoopCounter<1000;innerLoopCounter++){
                iterations = (short) (iterations + (short)1);
            }
        }

        //Map to bytes
        echoBytes[0] = (byte)(outerLoopCounter >> 8);
        echoBytes[1] = (byte)outerLoopCounter;
        echoBytes[2] = (byte)(innerLoopCounter >> 8);
        echoBytes[3] = (byte)innerLoopCounter;
        echoBytes[4] = (byte)(iterations >> 8);
        echoBytes[5] = (byte)iterations;

        apdu.setOutgoing();
        apdu.setOutgoingLength((short) (6 + 5));

        // echo header
        apdu.sendBytes((short) 0, (short) 5);

        // echo data
        apdu.sendBytesLong(echoBytes, (short) 0, (short) 6);
    }
}