log4j UdpAppender

package cappender;

import org.apache.log4j.AppenderSkeleton;
import org.apache.log4j.Layout;
import org.apache.log4j.helpers.LogLog;
import org.apache.log4j.spi.LoggingEvent;

import java.io.IOException;
import java.net.*;

public class UDPAppender extends AppenderSkeleton {
    static private int bufferSize = 8 * 1024;

    private byte data[];
    private String remoteHost = "localhost";
    private int port = 5000;

    private InetAddress address = null;
    private DatagramSocket dataSocket = null;
    private DatagramPacket dataPacket = null;

    public UDPAppender() {

    }

    private void init() {
        try {
            dataSocket = new DatagramSocket(this.port + 1);
            address = InetAddress.getByName(remoteHost);
        } catch (SocketException e) {
            LogLog.debug(e.getMessage());
        } catch (UnknownHostException e) {
            LogLog.debug(e.getMessage());
        }

        data = new byte[bufferSize];

        if (this.layout == null) {
            LogLog.debug("The layout is not loaded... we set it.");
            String pattern = "%-4r %-5p %d{yyyy-MM-dd HH:mm:ss} %c %m%n";
            this.setLayout(new org.apache.log4j.PatternLayout(pattern));
        }
    }

    @Override
    protected void append(LoggingEvent event) {
        try {
            data = subAppend(event).getBytes();
            dataPacket = new DatagramPacket(data, data.length, address, port);
            dataSocket.send(dataPacket);
        } catch (SocketException se) {
            se.printStackTrace();
        } catch (IOException ie) {
            ie.printStackTrace();
        }
    }

    private String subAppend(LoggingEvent event) {

        StringBuilder sb = new StringBuilder();
        String msg = this.layout.format(event);
        sb.append(msg);

        if (layout.ignoresThrowable()) {
            String[] s = event.getThrowableStrRep();
            if (s != null) {
                int len = s.length;
                for (int i = 0; i < len; i++) {
                    sb.append(s[i]);
                    sb.append(Layout.LINE_SEP);
                }
            }
        }
        return sb.toString();

    }

    /**
     * Derived appenders should override this method if option structure
     * requires it.
     */
    public void activateOptions() {
        init();
    }

    public void close() {
        if (closed)
            return;

        if (!dataSocket.isClosed()) {
            dataSocket.close();
        }
        closed = true;
    }

    public boolean requiresLayout() {
        return true;
    }

    /**
     * Returns value of the RemoteHost option.
     */
    public String getRemoteHost() {
        return remoteHost;
    }

    /**
     * The RemoteHost option takes a string value which should be the
     * host name of the server where a {@link String} is running.
     */
    public void setRemoteHost(String host) {
        String val = host.trim();
        remoteHost = val;
    }

    /**
     * Returns value of the Port option.
     */
    public int getPort() {
        return port;
    }

    /**
     * The Port option takes a positive integer representing the port
     * where the server is waiting for connections.
     */
    public void setPort(int port) {
        this.port = port;
    }
}