Java NIO UDP DatagramChannel数据未发送出去

时间:2014-08-27 08:50:12

标签: java sockets network-programming udp nio

我正在编写一个从端口获取数据的程序,将其保存到缓冲区中,当缓冲区已满时,它将使用另一个端口发送数据。该协议是UDP。

所以这是我的代码:

try {
    // UDP data-in settings
    DatagramChannel inChannel = DatagramChannel.open();
    SocketAddress inAddress = new InetSocketAddress(FMBuffer.IN_PORT);
    inChannel.bind(inAddress);

    // UDP data-out settings
    DatagramChannel outChannel = DatagramChannel.open();
    SocketAddress outAddress = new InetSocketAddress(FMBuffer.OUT_PORT);
    outChannel.bind(outAddress);

    LinkedList<ByteBuffer> buffer = new LinkedList<ByteBuffer>();
    ByteBuffer b = ByteBuffer
            .allocateDirect(FMBuffer.UDP_MAX_PACKET_SIZE);

    while (true) {          

        if (inChannel.receive(b) != null) { // Receive data and put into b
            b.flip();                   
            // Save b into the buffer
            buffer.addLast(b);

            System.out.print("In(" + buffer.size() + "): ");
            while (buffer.getLast().hasRemaining()) {                           
                System.out.write(buffer.getLast().get());
            }
            System.out.println();

            // If the buffer reaches the set limit
            if (buffer.size() > FMBuffer.BUFFER_LIST_SIZE) {
                // Send the first b out, then remove it
                System.out.print("Out(" + buffer.size() + "): ");
                while (buffer.getFirst().hasRemaining()) {                          
                    System.out.write(buffer.getFirst().get());
                    outChannel.send(buffer.getFirst(), outAddress);
                }
                System.out.println();
                buffer.removeFirst();
            }

            b.clear();

        } else { // Receive no data
            if (buffer.size() > 0) {
                // Send the first b out, then remove it
                System.out.print("Out remaining(" + buffer.size() + "): ");
                while (buffer.getFirst().hasRemaining()) {                          
                    System.out.write(buffer.getFirst().get());
                    outChannel.send(buffer.getFirst(), outAddress);
                }
                System.out.println();
                buffer.removeFirst();
            }
        }
    }
} catch (IOException e) {
    e.printStackTrace();
}

有几个问题......

  1. 我尝试使用程序从127.0.0.1:OUT_PORT读取。该计划表示该港口正在使用中。我该怎么办?

  2. 说BUFFER_LIST_SIZE = 5和outChannel.send(...)被评论。 输出数据始终为空白,而不是输入数据。 此外,如果我停止向其发送数据,它将不会从其缓冲区输出剩余数据。 通过输入“ * UDP Flood。服务器压力测试****”,它将输出:

  3. In(1): ***** UDP Flood. Server stress test ****
    In(2): ***** UDP Flood. Server stress test ****
    In(3): ***** UDP Flood. Server stress test ****
    In(4): ***** UDP Flood. Server stress test ****
    In(5): ***** UDP Flood. Server stress test ****
    In(6): ***** UDP Flood. Server stress test ****
    Out(6): 
    In(6): ***** UDP Flood. Server stress test ****
    Out(6): 
    In(6): ***** UDP Flood. Server stress test ****
    Out(6): 
    In(6): ***** UDP Flood. Server stress test ****
    Out(6): 
    

0 个答案:

没有答案