我有客户端服务器应用程序，当我运行服务器时，我得到从服务器类打印的内容，但是当我运行客户端类时，即使建立了连接也没有任何反应 但似乎 Client 类没有从服务器接收任何消息
这是我的服务器代码
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
ServerSocket provider;
Socket clientsocket;
OutputStream out;
InputStream in;
InetAddress clientAddress;
StringBuilder sb;
BufferedReader br;
String msg="";
Server(){
}
public void Communicate()
{
try {
provider=new ServerSocket(2013);
System.out.println("Server Waiting for connections");
clientsocket=provider.accept();
System.out.println("incoming connection from ");
clientAddress=clientsocket.getInetAddress();
//System.out.println("Client Name"+clientAddress.getHostName());
System.out.println("Client Address "+clientAddress.getHostAddress());
out=clientsocket.getOutputStream();
in=clientsocket.getInputStream();
sendmsg("connection success");
do
{
msg=read_instream(in);
System.out.println("client say"+msg);
if(msg.equals("bye"))
{
sendmsg(msg);
clientsocket.close();
in.close();
out.close();
}
}
while(!msg.equals("bye"));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void sendmsg(String msg) throws IOException
{
out.write(msg.getBytes());
out.flush();
}
private String read_instream(InputStream in) throws IOException
{
br=new BufferedReader(new InputStreamReader(in));
sb=new StringBuilder();
while (br.readLine()!=null)
sb.append(br.readLine());
return sb.toString();
}
public static void main(String[] args){
Server provider=new Server();
while(true)
provider.Communicate();
}
}
和客户端代码
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;
public class Client {
Socket client;
String msg="give me the last degree";
OutputStream out;
InputStream in;
StringBuilder sb;
BufferedReader br;
public void Communicate()
{
try {
client=new Socket("localhost",2013);
out=client.getOutputStream();
in=client.getInputStream();
System.out.println("Messege from server:"+read_instream(in));
while (!msg.equals("bye"))
{
msg=read_instream(in);
System.out.println("server say"+msg);
sendmsg("hey from client");
msg="bye";
sendmsg(msg);
}
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private String read_instream(InputStream in) throws IOException
{
br=new BufferedReader(new InputStreamReader(in));
sb=new StringBuilder();
while (br.readLine()!=null)
sb.append(br.readLine());
return sb.toString();
}
private void sendmsg(String msg) throws IOException
{
out.write(msg.getBytes());
out.flush();
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Client requester=new Client();
requester.Communicate();
}
}
最佳答案
您的 read_instream 方法将阻塞，直到流关闭。 br.readline() 在“到达流末尾”之前不会返回 null(请参阅 javadoc )。您的服务器类发送一条消息，刷新它，但永远不会结束流。
编辑:发生的情况仍然是一个阻塞问题。您的服务器仅在收到客户端返回的消息后才关闭到客户端的输出流。然而，服务器上的 read_instream() 方法等待客户端关闭流。客户端永远不会关闭它，因为它仍然在等待服务器关闭。因此一种选择是在 sendmsg() 方法中关闭输出流。然而，这将不允许发送任何其他消息。您还可以更改 read_instream() 方法以在每行之后返回，而不是让它等待流结束。
阅读 Oracle docs 中的客户端/服务器教程。他们使用第二个选项来进行服务器和客户端之间的长时间运行对话:不要等待 read_instream() 方法中的流结束。在教程结束时，他们将简要介绍如何支持多个客户端。
关于java - 客户端服务器不通信，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20152094/