我正在通过TCP sockat创建简单的聊天应用程序，但是当我尝试将数据发送到服务器进行登录时程序冻结，当我尝试调试客户端代码时，它停止在以Dataoutputstream.write开头的方法上 服务器代码
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* @author HADDAD
*/
public class Server {
final static int LOGIN=0,LOGOUT=1,BCAST=2,MCAST=3,SERVER=4;
private DataInputStream in;
private DataOutputStream out;
private Socket client;
private ServerSocket serverSocket;
private ArrayList<connection> conlist=new ArrayList<>();
private boolean running;
private byte[] bytes=new byte[1000];
private String msg;
private String[] msgs;
private int tag;
private static ServerGui serverGui=new ServerGui();
public void runServer()
{
serverGui.jTextArea1.append("CHAT SERVER STARTED");
running=true;
while(running)
{
try {
serverSocket =new ServerSocket(1676);
client =serverSocket.accept();
in=new DataInputStream(client.getInputStream());
// out=new DataOutputStream(client.getOutputStream());
in.read(bytes);
msg=new String(bytes);
msgs=msg.split("-");
tag=check(msgs);
switch(tag)
{
case LOGIN:
{
if(login(msgs[1], msgs[2], client)){}
else { System.out.println("login failed");
serverGui.jTextArea1.append("login failed");
}
break;
}
case LOGOUT:
{
if(logout(msgs[1])){}
else System.out.println("you are not logged in");
break;
}
case SERVER:
recivemsg(msgs[1], msgs[0]);
break;
case MCAST:
{
multiCast(msgs);
}
case BCAST:
{
broadCast(msgs);
}
}
} catch (IOException ex) {
Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
public int check(String[] data)
{
return Integer.parseInt(data[data.length-1]);
}
public boolean login(String usr,String pass,Socket s) throws IOException
{
connection con=new connection(s, usr);
if(1==1){
conlist.add(con);
writeMsgFromserver(con,true);
return true;}
else{
writeMsgFromserver(con, false);
return false;
}
}
public boolean logout(String usr)
{
for(connection c:conlist)
{
if(c.getUsername().equals(usr))
{
conlist.remove(c);
return true;
}
else return false;
}
return false;
}
public void recivemsg(String usr,String msg)
{
System.out.println(usr+":"+msg);
}
public void multiCast(String[] msgs) throws IOException
{
Socket s;
DataOutputStream dos;
if(conlist.isEmpty())
{
serverGui.jTextArea1.append(System.lineSeparator());
serverGui.jTextArea1.append("there is no other users");
System.out.println("there is no other users");
}
else
for(connection c:conlist)
{
s=c.getSocket();
dos=new DataOutputStream(s.getOutputStream());
dos.write(Format(msgs).getBytes());
}
}
public void writeMsgFromserver(connection c,boolean b) throws IOException
{
if(b==true){
String m="accept"+"-"+"Server"+"-"+"empty"+"-"+"empty"+"-"+SERVER;
Socket s=c.getSocket();
DataOutputStream dos=new DataOutputStream(s.getOutputStream());
dos.write(m.getBytes());
serverGui.jTextArea1.append(System.lineSeparator());
serverGui.jTextArea1.append("Server:"+c.getUsername()+" logged in");
}
else
{
String m="refuse"+"-"+"Server"+"-"+"empty"+"-"+"empty"+"-"+SERVER;
Socket s=c.getSocket();
DataOutputStream dos=new DataOutputStream(s.getOutputStream());
dos.write(m.getBytes());
serverGui.jTextArea1.append(System.lineSeparator());
serverGui.jTextArea1.append("Server:"+c.getUsername()+" registeration failed");
}
}
public void broadCast(String[] msgs) throws IOException
{
Socket rcvrsocket;
DataOutputStream dos;
for(connection c:conlist)
{
if(c.getUsername().equals(msgs[1]))
{
rcvrsocket=c.getSocket();
dos=new DataOutputStream(rcvrsocket.getOutputStream());
dos.write(Format(msgs).getBytes());
return ;
}
}
System.out.println("user:"+msgs[1]+"Not found!");
serverGui.jTextArea1.append(System.lineSeparator());
serverGui.jTextArea1.append("user:"+msgs[1]+"Not found!");
}
public String Format(String[] m)
{
StringBuilder builder=new StringBuilder();
for (int i=0;i<m.length;i++)
{
builder.append(m[i]);
if(i!=m.length-1)
builder.append('-');
}
return builder.toString();
}
public static void main(String[] args){
Server s=new Server();
serverGui.main(args);
s.runServer();
}
}
客户端代码
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* @author HADDAD
*/
public class client {
private String usrname;
private String pass;
private int port;
private Socket socket;
private DataInputStream dis;
private DataOutputStream dos;
private boolean loggedin=false;
private byte[] bytes;
private ClientGui cg;
public boolean isLoggedin() {
return loggedin;
}
public void setLoggedin(boolean loggedin) {
this.loggedin = loggedin;
}
public client(String usrname, String pass, int port,ClientGui cg) {
bytes=new byte[1000];
this.usrname = usrname;
this.pass = pass;
this.port = port;
this.cg=cg;
}
public void start() throws IOException{
socket =new Socket("localhost", port);
dis=new DataInputStream(socket.getInputStream());
dos=new DataOutputStream(socket.getOutputStream());
sendloginmsg();
dis.read(bytes);
String m=new String(bytes);
String msgs[]=recive(m);
if(msgs[1].equals("accept"))
{
cg.jTextArea1.append(System.lineSeparator());
cg.jTextArea1.append("logain successed");
}
else
{
cg.jTextArea1.append(System.lineSeparator());
cg.jTextArea1.append("logain failed check your username or password");
return;
}
while(true)
{
dis.read(bytes);
m=new String(bytes);
msgs=recive(m);
writeToGui(msgs);
}
}
public void sendMsg(String msg) throws IOException
{
dos.write(msg.getBytes());
dos.flush();
}
public String[] recive(String msg)
{
String[] msgs=msg.split("-");
String[] a={msgs[0],msgs[1],msgs[msgs.length-1]};
return a;
}
public void writeToGui(String[] mm)
{
switch(Integer.parseInt(mm[mm.length-1]))
{
case Server.SERVER:
{
cg.jTextArea1.append(System.lineSeparator());
cg.jTextArea1.append("Server:"+mm[0]);
break;
}
case Server.MCAST :
{
cg.jTextArea1.append(System.lineSeparator());
cg.jTextArea1.append(mm[1]+":"+mm[0]);
break;
}
case Server.BCAST:
{
cg.jTextArea1.append(System.lineSeparator());
cg.jTextArea1.append(mm[1]+":"+mm[0]);
break;
}
}
}
public void sendloginmsg() throws IOException
{
String tag=String.valueOf(Server.LOGIN);
String[] m={"Hello!",usrname,pass,"Server",tag};
sendMsg(Format(m));
}
public String Format(String[] m)
{
StringBuilder builder=new StringBuilder();
for (int i=0;i<m.length;i++)
{
builder.append(m[i]);
if(i!=m.length-1)
builder.append('-');
}
return builder.toString();
}
}
连接代码
import java.net.Socket;
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* @author HADDAD
*/
public class connection {
private Socket socket;
private String username;
public connection(Socket socket, String username) {
this.socket = socket;
this.username = username;
}
public Socket getSocket() {
return socket;
}
public String getUsername() {
return username;
}
}
sendMsg()方法时发生和死锁
答案 0 :(得分：1)
如果您对DataOutputStream的写入阻止，则通常意味着另一端未读取。
我建议在客户端添加一个单独的线程，它只会在服务器的另一端读取DataInputStream，直到连接关闭。此读者线程可以使用SwingUtils.invokeLater（）
为事件循环计划事件注意：这意味着您应该从新线程调用start()，并且您对GUI的所有更新都应通过invokeLater()