How to restrict the size of Buffer data object

Question

Hi everyone.
How do you restrict the size of the Buffer data object. The byte array that you get by calling getData(). I want to restrict the size to be at most X nbr of bytes. I'm 'filling' the buffer like this:
Buffer readBuffer;
PushBufferStream stream;
stream.read(readBuffer);

Answer 1

This is my code:
class DataSourceHandler implements DataSink, BufferTransferHandler {
          private int MAX_DATA_PACKET_SIZE = 2000;
          private DataSource source;
          private PullBufferStream pullStrms[] = null;
          private PushBufferStream pushStrms[] = null;
          // Data sink listeners.
          private Vector listeners = new Vector(1);
          // Stored all the streams that are not yet finished (i.e. EOM
          // has not been received.
          private SourceStream unfinishedStrms[] = null;
          // Loop threads to pull data from a PullBufferDataSource.
          // There is one thread per each PullSourceStream.
          private Loop loops[] = null;
          private Buffer readBuffer;
           * Sets the media source this <code>MediaHandler</code> should use to
           * obtain content.
          public void setSource(DataSource source)
                    throws IncompatibleSourceException {
               // Different types of DataSources need to handled differently.
               if (source instanceof PushBufferDataSource) {
                    System.out.println("source instanceof PushBufferDataSource");
                    pushStrms = ((PushBufferDataSource) source).getStreams();
                    unfinishedStrms = new SourceStream[pushStrms.length];
                    // Set the transfer handler to receive pushed data from
                    // the push DataSource.
                    for (int i = 0; i < pushStrms.length; i++) {
                         pushStrms.setTransferHandler(this);
                         unfinishedStrms[i] = pushStrms[i];
               } else if (source instanceof PullBufferDataSource) {
                    System.out.println("source instanceof PullBufferDataSource");
                    pullStrms = ((PullBufferDataSource) source).getStreams();
                    unfinishedStrms = new SourceStream[pullStrms.length];
                    // For pull data sources, we'll start a thread per
                    // stream to pull data from the source.
                    loops = new Loop[pullStrms.length];
                    for (int i = 0; i < pullStrms.length; i++) {
                         loops[i] = new Loop(this, pullStrms[i]);
                         unfinishedStrms[i] = pullStrms[i];
               } else {
                    // This handler only handles push or pull buffer datasource.
                    throw new IncompatibleSourceException();
               this.source = source;
               readBuffer = new Buffer();
               byte[] data = new byte[MAX_DATA_PACKET_SIZE];
               readBuffer.setData(data);
          * For completeness, DataSink's require this method. But we don't need
          * it.
          public void setOutputLocator(MediaLocator ml) {
          public MediaLocator getOutputLocator() {
               return null;
          public String getContentType() {
               return source.getContentType();
          * Our DataSink does not need to be opened.
          public void open() {
          public void start() {
               try {
                    source.start();
               } catch (IOException e) {
                    System.err.println(e);
               // Start the processing loop if we are dealing with a
               // PullBufferDataSource.
               if (loops != null) {
                    for (int i = 0; i < loops.length; i++)
                         loops[i].restart();
          public void stop() {
               try {
                    source.stop();
               } catch (IOException e) {
                    System.err.println(e);
               // Start the processing loop if we are dealing with a
               // PullBufferDataSource.
               if (loops != null) {
                    for (int i = 0; i < loops.length; i++)
                         loops[i].pause();
          public void close() {
               stop();
               if (loops != null) {
                    for (int i = 0; i < loops.length; i++)
                         loops[i].kill();
          public void addDataSinkListener(DataSinkListener dsl) {
               if (dsl != null)
                    if (!listeners.contains(dsl))
                         listeners.addElement(dsl);
          public void removeDataSinkListener(DataSinkListener dsl) {
               if (dsl != null)
                    listeners.removeElement(dsl);
          protected void sendEvent(DataSinkEvent event) {
               if (!listeners.isEmpty()) {
                    synchronized (listeners) {
                         Enumeration list = listeners.elements();
                         while (list.hasMoreElements()) {
                              DataSinkListener listener = (DataSinkListener) list
                                        .nextElement();
                              listener.dataSinkUpdate(event);