Serial or java string conversion bug?

Java code. Requires the gnu.io.rxtx library for serial capabilities.

import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.TooManyListenersException;


public class Arduino {
    private SerialPort serialPort;
    private InputStream input;
    private OutputStream output;

    public Arduino(String portname, int baud) throws Exception {
        CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier("COM5");
        if (portIdentifier.isCurrentlyOwned()) {
            throw new Exception("Port currently in use.");
        } else {
            serialPort = (SerialPort)portIdentifier.open("Java", 2000);
            serialPort.setSerialPortParams(baud, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);

            input = serialPort.getInputStream();
            output = serialPort.getOutputStream();

            Thread.sleep(2000);
        }
    }

    public synchronized int hasavailable() throws IOException {
        return input.available();
    }

    public synchronized byte[] read(int size) throws IOException {
        byte[] data = new byte[size];
        input.read(data);
        return data;
    }

    public synchronized boolean write(String data) {
        return write(data.getBytes());
    }
    public synchronized boolean write(byte data) {
        return write(new byte[] {data});
    }
    public synchronized boolean write(byte[] data) {
        try {
            output.write(data);
            output.flush();
        } catch (IOException e) {
            return false;
        }
        return true;
    }

    public void attachSerialListener(SerialPortEventListener l) throws TooManyListenersException {
        serialPort.addEventListener(l);
    }

    public synchronized void close() throws IOException {
        serialPort.removeEventListener();
        serialPort.close();
        input.close();
        output.close();
    }

    public static void main(String[] args) {
        try {
            final Arduino board = new Arduino("COM5", 9600);
            Thread.sleep(2000);
            BufferedWriter rom = new BufferedWriter(new FileWriter("R-TYPE DX.gb"));
            board.write((byte)0);
            System.out.println("Buffering...");
            Thread.sleep(1000);
            System.out.print("Reading...");
            while (board.hasavailable() > 0)
                rom.write(new String(board.read(board.hasavailable())));
            System.out.println("Done.");
            rom.flush();
            rom.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        System.exit(0);
    }
}

Arduino code - simple burn and leave.
void setup() {
    Serial.begin(9600);
}


void loop() {
    if (Serial.available() > 0)
        if (Serial.read() == 0)
          for (unsigned int b=0; b<256; b++)
              Serial.write(b);
}