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;    }}