如何在套接字通道中發送和接收序列化對象

Question

我想通過套接字通道傳輸序列化對象。 我希望將“Hi friend”字符串作為序列化對象，然后在套接字通道中寫入此對象，而在另一端我想讀取相同的對象並檢索數據。

我想用Java SocketChannel做的所有這些事情。 這該怎么做？ 我嘗試過如下，但沒有在接收方獲得任何數據。

private static void writeObject(Object obj, SelectionKey selectionKey) {
    ObjectOutputStream oos;
    try {
        SocketChannel channel = (SocketChannel) selectionKey.channel();
        oos = new ObjectOutputStream(Channels.newOutputStream(channel));

        oos.writeObject(obj);
    } catch (IOException ex) {
        ex.printStackTrace();
    }
}

private static Object readObject(SelectionKey selectionKey) {
    ObjectInputStream ois;
    Object obj = new Object();
    SocketChannel channel = (SocketChannel) selectionKey.channel();
    try {
        ois = new ObjectInputStream(Channels.newInputStream(channel));
        obj = ois.readObject();
    } catch (Exception ex) {
        ex.printStackTrace();
    }
    return obj;
}

Answer 1

您的SocketChannel處理似乎不完整，請參閱SocketChannels傳輸字節的完整示例：

/*
 * Writer
 */
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.net.InetSocketAddress;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;

public class Sender {
    public static void main(String[] args) throws IOException {
        System.out.println("Sender Start");

        ServerSocketChannel ssChannel = ServerSocketChannel.open();
        ssChannel.configureBlocking(true);
        int port = 12345;
        ssChannel.socket().bind(new InetSocketAddress(port));

        String obj ="testtext";
        while (true) {
            SocketChannel sChannel = ssChannel.accept();

            ObjectOutputStream  oos = new 
                      ObjectOutputStream(sChannel.socket().getOutputStream());
            oos.writeObject(obj);
            oos.close();

            System.out.println("Connection ended");
        }
    }
}

和讀者

/*
 * Reader
 */
import java.io.IOException;
import java.io.ObjectInputStream;
import java.net.InetSocketAddress;
import java.nio.channels.SocketChannel;

public class Receiver {
    public static void main(String[] args) 
    throws IOException, ClassNotFoundException {
        System.out.println("Receiver Start");

        SocketChannel sChannel = SocketChannel.open();
        sChannel.configureBlocking(true);
        if (sChannel.connect(new InetSocketAddress("localhost", 12345))) {

            ObjectInputStream ois = 
                     new ObjectInputStream(sChannel.socket().getInputStream());

            String s = (String)ois.readObject();
            System.out.println("String is: '" + s + "'");
        }

        System.out.println("End Receiver");
    }
}

當您第一次啟動服務器，然后啟動接收器時，您將獲得以下輸出：

服務器的控制台

Sender Start
Connection ended

接收器的控制台

Receiver Start
String is: 'testtext'
End Receiver

這不是最好的解決方案，但是遵循使用Java的ServerSocketChannel