我正在尝试编写一个投标应用程序，并有一个服务器(和线程处理程序)和客户端(和客户端处理程序)。 目前，多个客户端可以正常连接，但第一个连接的客户端会获取开始消息，并且只有在第一个客户端进行第三次交互(客户端和服务器之间)后，列表中的下一个客户端才会获取开始消息。 我不完全确定是什么原因造成的，因为它每次都会添加一个新线程。它只是没有同时向所有客户端显示 writeUTF() 的内容。
我想知道我做错了什么，以及为什么我无法让多个客户同时开始拍卖。这是我的代码。 客户端线程和客户端
import java.net.*;
import java.io.*;
import java.util.*;
public class Client implements Runnable
{ private Socket socket = null;
private Thread thread = null;
private BufferedReader console = null;
private DataOutputStream streamOut = null;
private ClientThread client = null;
private String chatName;
public Client(String serverName, int serverPort, String name)
{
System.out.println("Establishing connection. Please wait ...");
this.chatName = name;
try{
socket = new Socket(serverName, serverPort);
System.out.println("Connected: " + socket);
start();
}
catch(UnknownHostException uhe){
System.out.println("Host unknown: " + uhe.getMessage());
}
catch(IOException ioe){
System.out.println("Unexpected exception: " + ioe.getMessage());
}
}
public void run()
{
while (thread != null){
try {
//String message = chatName + " > " + console.readLine();
String message = console.readLine();
streamOut.writeUTF(message);
streamOut.flush();
}
catch(IOException ioe)
{ System.out.println("Sending error: " + ioe.getMessage());
stop();
}
}
}
public void handle(String msg)
{ if (msg.equals(".bye"))
{ System.out.println("Good bye. Press RETURN to exit ...");
stop();
}
else
System.out.println(msg);
}
public void start() throws IOException
{
console = new BufferedReader(new InputStreamReader(System.in));
streamOut = new DataOutputStream(socket.getOutputStream());
if (thread == null)
{ client = new ClientThread(this, socket);
thread = new Thread(this);
thread.start();
}
}
public void stop()
{
try
{ if (console != null) console.close();
if (streamOut != null) streamOut.close();
if (socket != null) socket.close();
}
catch(IOException ioe)
{
System.out.println("Error closing ...");
}
client.close();
thread = null;
}
public static void main(String args[])
{ Client client = null;
if (args.length != 3)
System.out.println("Usage: java Client host port name");
else
client = new Client(args[0], Integer.parseInt(args[1]), args[2]);
}
}
import java.net.*;
import java.io.*;
import java.util.*;
import java.net.*;
客户端线程
public class ClientThread extends Thread
{ private Socket socket = null;
private Client client = null;
private DataInputStream streamIn = null;
private DataOutputStream streamOut = null;
private BufferedReader console;
private String message, bidMessage;
public ClientThread(Client _client, Socket _socket)
{ client = _client;
socket = _socket;
open();
start();
}
public void open()
{ try
{
streamIn = new DataInputStream(socket.getInputStream());
String auction = streamIn.readUTF(); // Commence auction/
System.out.println(auction);
String item = streamIn.readUTF();
System.out.println(item);
Scanner scanner = new Scanner(System.in);
streamOut = new DataOutputStream(socket.getOutputStream());
message = scanner.next();
streamOut.writeUTF(message);
streamOut.flush();
String reply = streamIn.readUTF();
System.out.println(reply);
bidMessage = scanner.next();
streamOut.writeUTF(bidMessage);
streamOut.flush();
}
catch(IOException ioe)
{
System.out.println("Error getting input stream: " + ioe);
client.stop();
}
}
public void close()
{ try
{ if (streamIn != null) streamIn.close();
}
catch(IOException ioe)
{ System.out.println("Error closing input stream: " + ioe);
}
}
public void run()
{
while (true && client!= null){
try {
client.handle(streamIn.readUTF());
}
catch(IOException ioe)
{
client = null;
System.out.println("Listening error: " + ioe.getMessage());
}
}
}
}
出价服务器
import java.net.*;
import java.io.*;
public class BidServer implements Runnable
{
// Array of clients
private BidServerThread clients[] = new BidServerThread[50];
private ServerSocket server = null;
private Thread thread = null;
private int clientCount = 0;
public BidServer(int port)
{
try {
System.out.println("Binding to port " + port + ", please wait ...");
server = new ServerSocket(port);
System.out.println("Server started: " + server.getInetAddress());
start();
}
catch(IOException ioe)
{
System.out.println("Can not bind to port " + port + ": " + ioe.getMessage());
}
}
public void run()
{
while (thread != null)
{
try{
System.out.println("Waiting for a client ...");
addThread(server.accept());
int pause = (int)(Math.random()*3000);
Thread.sleep(pause);
}
catch(IOException ioe){
System.out.println("Server accept error: " + ioe);
stop();
}
catch (InterruptedException e){
System.out.println(e);
}
}
}
public void start()
{
if (thread == null) {
thread = new Thread(this);
thread.start();
}
}
public void stop(){
thread = null;
}
private int findClient(int ID)
{
for (int i = 0; i < clientCount; i++)
if (clients[i].getID() == ID)
return i;
return -1;
}
public synchronized void broadcast(int ID, String input)
{
if (input.equals(".bye")){
clients[findClient(ID)].send(".bye");
remove(ID);
}
else
for (int i = 0; i < clientCount; i++){
if(clients[i].getID() != ID)
clients[i].send(ID + ": " + input); // sends messages to clients
}
notifyAll();
}
public synchronized void remove(int ID)
{
int pos = findClient(ID);
if (pos >= 0){
BidServerThread toTerminate = clients[pos];
System.out.println("Removing client thread " + ID + " at " + pos);
if (pos < clientCount-1)
for (int i = pos+1; i < clientCount; i++)
clients[i-1] = clients[i];
clientCount--;
try{
toTerminate.close();
}
catch(IOException ioe)
{
System.out.println("Error closing thread: " + ioe);
}
toTerminate = null;
System.out.println("Client " + pos + " removed");
notifyAll();
}
}
private void addThread(Socket socket) throws InterruptedException
{
if (clientCount < clients.length){
System.out.println("Client accepted: " + socket);
clients[clientCount] = new BidServerThread(this, socket);
try{
clients[clientCount].open();
clients[clientCount].start();
clientCount++;
}
catch(IOException ioe){
System.out.println("Error opening thread: " + ioe);
}
}
else
System.out.println("Client refused: maximum " + clients.length + " reached.");
}
public static void main(String args[]) {
BidServer server = null;
if (args.length != 1)
System.out.println("Usage: java BidServer port");
else
server = new BidServer(Integer.parseInt(args[0]));
}
}
出价服务器线程
import java.net.*;
import java.awt.List;
import java.io.*;
import java.awt.*;
import java.util.*;
import java.util.concurrent.BrokenBarrierException;
public class BidServerThread extends Thread
{ private BidServer server = null;
private Socket socket = null;
private int ID = -1;
private DataInputStream streamIn = null;
private DataOutputStream streamOut = null;
private Thread thread;
private String auctionStart, bid,bidMade,clientBid;
private String invalidBid;
int firstVal;
ArrayList<Bid> items = new ArrayList<Bid>();
//items.add(new Bid());
//items
//items
//items.add(new Bid("Red Bike",0));
public BidServerThread(BidServer _server, Socket _socket)
{
super();
server = _server;
socket = _socket;
ID = socket.getPort();
}
public void send(String msg)
{
try{
streamOut.writeUTF(msg);
streamOut.flush();
}
catch(IOException ioe)
{
System.out.println(ID + " ERROR sending: " + ioe.getMessage());
server.remove(ID);
thread=null;
}
}
public int getID(){
return ID;
}
public void run()
{
System.out.println("Server Thread " + ID + " running.");
thread = new Thread(this);
while (true){
try{
server.broadcast(ID, streamIn.readUTF());
int pause = (int)(Math.random()*3000);
Thread.sleep(pause);
}
catch (InterruptedException e)
{
System.out.println(e);
}
catch(IOException ioe){
System.out.println(ID + " ERROR reading: " + ioe.getMessage());
server.remove(ID);
thread = null;
}
}
}
public void open() throws IOException, InterruptedException
{
streamIn = new DataInputStream(new
BufferedInputStream(socket.getInputStream()));
streamOut = new DataOutputStream(new
BufferedOutputStream(socket.getOutputStream()));
String msg2 = "Welcome to the auction,do you wish to start?";
streamOut.writeUTF(msg2);
streamOut.flush();
String auctionStart;
String bid;
String firstMessage = streamIn.readUTF().toLowerCase();
CharSequence yes ="yes";
CharSequence no = "no";
if(firstMessage.contains(yes))
{
commenceBid();
}
else if(firstMessage.contains(no))
{
auctionStart ="Unfortunately, you cannot proceed. Closing connection";
System.out.println(auctionStart);
streamOut.writeUTF(auctionStart);
streamOut.flush();
int pause = (int)(Math.random()*2000);
Thread.sleep(pause);
socket.close();
}
else if(!firstMessage.contains(yes) && !firstMessage.contains(no))
{
System.out.println("Client has entered incorrect data");
open();
}
}
private void commenceBid() throws IOException {
items.add(new Bid("Yellow Bike",0));
items.add(new Bid("Red Bike",0));
//items.add(new Bid("Green bike",0));
String auctionStart = "Auction will commence now. First item is:\n" + items.get(0).getName();
String bidCommence = "Make a bid, whole number please.";
synchronized (server) {
server.broadcast(ID, bidCommence);
}
System.out.println("item value is" + items.get(0).getValue());
streamOut.writeUTF(auctionStart);
streamOut.flush();
streamOut.writeUTF(bidCommence);
streamOut.flush();
bidMade();
}
private void bidMade() throws IOException {
bidMade = streamIn.readUTF();
if(bidMade.matches(".*\\d.*"))
{
int bid = Integer.parseInt(bidMade);
if(bid <= items.get(0).getValue())
{
String lowBid = "Latest bid is too low, please bid higher than the current bid " + items.get(0).getValue();
streamOut.writeUTF(lowBid);
streamOut.flush();
commenceBid();
}
if (bid > items.get(0).getValue()) {
items.get(0).setValue(bid);
String bidItem = "value of current bid is: " + items.get(0).getValue();
streamOut.writeUTF(bidItem);
streamOut.flush();
System.out.println("Current bid: " + items.get(0).getValue());
String continueBid = "If you want to make another bid, say yes";
streamOut.writeUTF(continueBid);
String continueBidReply = streamIn.readUTF();
{
if(continueBidReply.contains("yes") || continueBidReply.contains("Yes"))
{
commenceBid();
}
if(continueBidReply.contains("No") || continueBidReply.contains("No"))
{
socket.close();
}
}
streamOut.flush();
}
}
else
{
invalidBid = "You have made an invalid bid, please choose a number";
streamOut.writeUTF(invalidBid);
streamOut.flush();
}
}
public void close() throws IOException
{
if (socket != null)
socket.close();
if (streamIn != null)
streamIn.close();
if (streamOut != null)
streamOut.close();
}
}
最佳答案
BidServerThread.open() 在 BidServer.addThread() 中启动线程之前调用。这会阻止 BidServer(并阻止其接受其他客户端)，直到调用返回。
BidServerThread.open() 执行与客户端交互的各种同步操作(“您希望开始吗？”、"is"/“否”等)。它最终递归地调用自身(循环)，并调用 commenceBid()，而 commenceBid() 又可能调用 bidMade()，而 bidMade() 又可能在与客户端的同步交互过程中递归到 commenceBid()。在这种情况下，您可能会在结束之前进行 3 次交互。
我想，您可以从 BidServerThread.run() 而不是在 BidServer.addThread() 中调用 BidServerThread.open() ，以便它在其线程中异步运行。 (Thread.start() 调用 Thread.run()。)
关于java - 多个客户端线程可以连接，线程按顺序接受，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20000703/