客户端while循环从服务器发送和接收

Question

This is my client application that is connected to a server. I use an object called DataPackage to send information back and forth. The code runs in its own thread.

The variable in is an ObjectInputStream and out is an ObjectOutputStream .

DataPackage dp = null;
while (true) {

    try {
        dp = (DataPackage) in.readObject();
        if (dp != null) {
            // Do stuff with received object
        }

        if (sendSomething) { // Send stuff
            out.writeObject( new DataPackage("some data") );
            out.flush();
            out.reset();
        }
    } catch (ClassNotFoundException | IOException e1) {
        e1.printStackTrace();
    }

    try {
        t.sleep(50);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}

The problem with my code is that I never reach the part where I send stuff, unless I receive something from the server. The loop waits for something from the server before it continues to if (sendSomething) . How should I structure my code so that I can send stuff any time and receive stuff any time? I hope you understand.

Answer 1

You can use the threads. If they use the same socket to communicate with an external server, this is common because they won't block while waiting to read from the socket.

Thread1:

block on read on recieve message - do something

Thread2: do things on something happening - write to socket

Answer 2

The line dp = (DataPackage) in.readObject(); is blocking. It means that it will not complete execution of lines below until it receives some reply from server.

One advise, create a new thread and pass instance of dp = (DataPackage) in.readObject(); so it won't block.