Пример #1
0
  /**
   * Copies the content of the most recently received packet into <tt>data</tt>.
   *
   * @param buffer an optional <tt>Buffer</tt> instance associated with the specified <tt>data</tt>,
   *     <tt>offset</tt> and <tt>length</tt> and provided to the method in case the implementation
   *     would like to provide additional <tt>Buffer</tt> properties such as <tt>flags</tt>
   * @param data the <tt>byte[]</tt> that we'd like to copy the content of the packet to.
   * @param offset the position where we are supposed to start writing in <tt>data</tt>.
   * @param length the number of <tt>byte</tt>s available for writing in <tt>data</tt>.
   * @return the number of bytes read
   * @throws IOException if <tt>length</tt> is less than the size of the packet.
   */
  protected int read(Buffer buffer, byte[] data, int offset, int length) throws IOException {
    if (data == null) throw new NullPointerException("data");

    if (ioError) return -1;

    RawPacket pkt;

    synchronized (pktSyncRoot) {
      pkt = this.pkt;
      this.pkt = null;
    }

    int pktLength;

    if (pkt == null) {
      pktLength = 0;
    } else {
      // By default, pkt will be returned to the pool after it was read.
      boolean poolPkt = true;

      try {
        pktLength = pkt.getLength();
        if (length < pktLength) {
          /*
           * If pkt is still the latest RawPacket made available to
           * reading, reinstate it for the next invocation of read;
           * otherwise, return it to the pool.
           */
          poolPkt = false;
          throw new IOException("Input buffer not big enough for " + pktLength);
        } else {
          byte[] pktBuffer = pkt.getBuffer();

          if (pktBuffer == null) {
            throw new NullPointerException(
                "pkt.buffer null, pkt.length " + pktLength + ", pkt.offset " + pkt.getOffset());
          } else {
            System.arraycopy(pkt.getBuffer(), pkt.getOffset(), data, offset, pktLength);
            if (buffer != null) buffer.setFlags(pkt.getFlags());
          }
        }
      } finally {
        if (!poolPkt) {
          synchronized (pktSyncRoot) {
            if (this.pkt == null) this.pkt = pkt;
            else poolPkt = true;
          }
        }
        if (poolPkt) {
          // Return pkt to the pool because it was successfully read.
          poolRawPacket(pkt);
        }
      }
    }

    return pktLength;
  }
Пример #2
0
  /**
   * Adds a <tt>DatagramPacketFilter</tt> which allows dropping <tt>DatagramPacket</tt>s before they
   * are converted into <tt>RawPacket</tt>s.
   *
   * @param datagramPacketFilter the <tt>DatagramPacketFilter</tt> which allows dropping
   *     <tt>DatagramPacket</tt>s before they are converted into <tt>RawPacket</tt>s
   */
  public synchronized void addDatagramPacketFilter(DatagramPacketFilter datagramPacketFilter) {
    if (datagramPacketFilter == null) throw new NullPointerException("datagramPacketFilter");

    if (datagramPacketFilters == null) {
      datagramPacketFilters = new DatagramPacketFilter[] {datagramPacketFilter};
    } else {
      final int length = datagramPacketFilters.length;

      for (int i = 0; i < length; i++)
        if (datagramPacketFilter.equals(datagramPacketFilters[i])) return;

      DatagramPacketFilter[] newDatagramPacketFilters = new DatagramPacketFilter[length + 1];

      System.arraycopy(datagramPacketFilters, 0, newDatagramPacketFilters, 0, length);
      newDatagramPacketFilters[length] = datagramPacketFilter;
      datagramPacketFilters = newDatagramPacketFilters;
    }
  }