Problem interfacing with Java

I followed the Interfacing with Java tutorial http://www.arduino.cc/playground/Interfacing/Java, but ran into some problems on testing. Currently my Arduino program works fine when I try with manual inputs.

Segment of C Code on Arduino:

...

char line[20];
int line_pos = 0;
char action[10];
unsigned long duration;
boolean data_ready = false;

void setup()
{
  Serial.begin(9600);
  delay(1500);
  Serial.println("Ready!");
}

void loop()
{
    char state;
    if(Serial.available()>0)
    {
        delay(20);
        state = Serial.read();
        
        if(state == '!')
        {
          data_ready = true;
          line[line_pos] = state;
          line_pos = 0;
        }
        else
        {
          line[line_pos] = state;
          line_pos = line_pos + 1;
        }
        
        if(data_ready == true)
        {
            split(line);
            Serial.print(action);
            delay(20);
            Serial.print("!");
            delay(20);
            Serial.print(duration);
            delay(20);
            Serial.print("!");
            
            Serial.println("Data has been split");

            if(strcmp(action, "left") == 0)
            {
                Serial.println("Received left");
            }
            else if(strcmp(action, "right") == 0)
            {
                Serial.println("Received rightt");
            }
            else if(strcmp(action, "straight") == 0)
            {
                Serial.println("Received straight");
            }
            
            memset(line, 0, 20);
            data_ready = false;
        }
    }
}  

void split(char input[20])
{
    char *param, *ptr;
    
    param = strtok_r(input, "#", &ptr);
    strncpy(action, param, sizeof(action));
    action[sizeof(action)-1] = '\0';
    
    param = strtok_r(NULL, "!", &ptr);
    duration = strtoul(param, ¶m, 10);
}

...

When I input "left#123!" I get the following output in the COM which is what I expected. No problems here:

Ready! left!123!Data has been split Received left

Now here's my Java code:

import java.io.InputStream;
import java.io.OutputStream;
import gnu.io.CommPortIdentifier; 
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent; 
import gnu.io.SerialPortEventListener; 
import java.util.Enumeration;

public class SerialTest implements SerialPortEventListener {
    SerialPort serialPort;
        /** The port we're normally going to use. */
    private static final String PORT_NAMES[] = { 
            "/dev/tty.usbserial-A9007UX1", // Mac OS X
            "/dev/ttyUSB0", // Linux
            "COM3", // Windows
            };
    /** Buffered input stream from the port */
    private InputStream input;
    /** The output stream to the port */
    private OutputStream output;
    /** Milliseconds to block while waiting for port open */
    private static final int TIME_OUT = 2000;
    /** Default bits per second for COM port. */
    private static final int DATA_RATE = 9600;

    private String display = "";

    public void initialize() {
        CommPortIdentifier portId = null;
        Enumeration portEnum = CommPortIdentifier.getPortIdentifiers();

        // iterate through, looking for the port
        while (portEnum.hasMoreElements()) {
            CommPortIdentifier currPortId = (CommPortIdentifier) portEnum.nextElement();
            for (String portName : PORT_NAMES) {
                if (currPortId.getName().equals(portName)) {
                    portId = currPortId;
                    break;
                }
            }
        }

        if (portId == null) {
            System.out.println("Could not find COM port.");
            return;
        }

        try {
            // open serial port, and use class name for the appName.
            serialPort = (SerialPort) portId.open(this.getClass().getName(),
                    TIME_OUT);

            // set port parameters
            serialPort.setSerialPortParams(DATA_RATE,
                    SerialPort.DATABITS_8,
                    SerialPort.STOPBITS_1,
                    SerialPort.PARITY_NONE);

            // open the streams
            input = serialPort.getInputStream();
            output = serialPort.getOutputStream();

            // add event listeners
            serialPort.addEventListener(this);
            serialPort.notifyOnDataAvailable(true);
        } catch (Exception e) {
            System.err.println(e.toString());
        }
    }

    /**
     * This should be called when you stop using the port.
     * This will prevent port locking on platforms like Linux.
     */
    public synchronized void close() {
        if (serialPort != null) {
            serialPort.removeEventListener();
            serialPort.close();
        }
    }

    /**
     * Handle an event on the serial port. Read the data and print it.
     */
    public synchronized void serialEvent(SerialPortEvent oEvent) {
        if (oEvent.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
            try {
                int available = input.available();
                byte chunk[] = new byte[available];
                input.read(chunk, 0, available);

                System.out.println(display);

                display += (new String(chunk)).trim();
                if(display.contains("!"))
                {
                    display = display.substring(0, display.indexOf("!"));

                    if(display.equals("Ready"))
                    {
                        String reply = "left#123!";
                        byte reply_byte[] = new byte[reply.length()];
                        reply_byte = reply.getBytes("UTF-16LE");
                        output.write(reply_byte);
                    }

                    display = "";
                }

            } catch (Exception e) {
                System.err.println(e.toString());
            }
        }
        // Ignore all the other eventTypes, but you should consider the other ones.
    }

    public static void main(String[] args) throws Exception {
        SerialTest main = new SerialTest();
        main.initialize();
        System.out.println("Started");
    }
}

Here's what Java code prints out in console:

Rea l 0 Data Datahas Datahasbee Datahasbeen sp Datahasbeen split

The serial input doesn't seem to be read fluidly, but in repeating parts. Can anybody help me diagnose the problem and give me a solution?