用java编写程序，实现基于TCP/IP协议的Socket通信过程。服务器端开放： IP地址：127.0.0.1 端口号：8889 客户端发送数据： Hello Server!

好的，我可以帮您解答这个问题。

以下是服务器端的Java代码示例：

import java.net.*;
import java.io.*;

public class Server {
    public static void main(String[] args) throws IOException {
        int portNumber = 8889;

        try (
            ServerSocket serverSocket =
                new ServerSocket(portNumber);
            Socket clientSocket = serverSocket.accept();     
            PrintWriter out =
                new PrintWriter(clientSocket.getOutputStream(), true);                   
            BufferedReader in = new BufferedReader(
                new InputStreamReader(clientSocket.getInputStream()));
        ) {
            String inputLine;
            while ((inputLine = in.readLine()) != null) {
                System.out.println("Received message from client: " + inputLine);
                out.println("Server received your message: " + inputLine);
            }
        } catch (IOException e) {
            System.out.println("Exception caught when trying to listen on port "
                + portNumber + " or listening for a connection");
            System.out.println(e.getMessage());
        }
    }
}

以下是客户端的Java代码示例：

import java.net.*;
import java.io.*;

public class Client {
    public static void main(String[] args) throws IOException {

        String hostName = "127.0.0.1";
        int portNumber = 8889;

        try (
            Socket socket = new Socket(hostName, portNumber);
            PrintWriter out =
                new PrintWriter(socket.getOutputStream(), true);
            BufferedReader in =
                new BufferedReader(
                    new InputStreamReader(socket.getInputStream()));
            BufferedReader stdIn =
                new BufferedReader(
                    new InputStreamReader(System.in))
        ) {
            String userInput;
            while ((userInput = stdIn.readLine()) != null) {
                out.println(userInput);
                System.out.println("Server response: " + in.readLine());
            }
        } catch (UnknownHostException e) {
            System.err.println("Don't know about host " + hostName);
            System.exit(1);
        } catch (IOException e) {
            System.err.println("Couldn't get I/O for the connection to " +
                hostName);
            System.exit(1);
        } 
    }
}

您可以先运行服务器端程序，然后再运行客户端程序，在客户端程序中输入"Hello Server!"，就可以发送数据给服务器端了。服务器端程序会接收到数据并返回相应的信息给客户端，客户端会输出服务器端返回的信息。