【发布时间】：2023-03-22 20:25:01
【问题描述】：
谁能告诉我我哪里错了为什么这个 RMI 聊天应用程序不起作用，目标是通过远程对象或序列化对象实现客户端、服务器和逻辑之间的解耦。
import javax.swing.*;
import java.awt.event.*;
import java.rmi.*;
import java.rmi.server.*;
public class ChatClient1 implements ICallback {
JFrame frame = new JFrame("Chat Client");
private JTextArea myText;
private static JTextArea TAUinDispMsg;
private JScrollPane myTextScroll;
private JScrollPane TAUinDispMsgScroll;
private String textString = "";
private boolean firstMessage = true;
private static String name = null;
private static final int HOR_SIZE = 400;
private static final int VER_SIZE = 150;
protected static ServerServices chatServer;
MessageImpl remomsg ;
public ChatClient1() throws RemoteException {
super();
try {
this.chatServer = (ServerServices) Naming.lookup("rmi://localhost"
+ "/ChatServer");
UnicastRemoteObject.exportObject(this);
chatServer.register(this);
} catch (Exception e) {
System.err.println("RemoteException: " + e.getMessage());
System.exit(0);
}
;
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
initComponents();
}
});
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
try {
if (name != null) {
// chatServer.leave(displayChat, name);
}
} catch (Exception ex) {
TAUinDispMsg.append("Exit failed.");
}
System.exit(0);
}
});
}
private void initComponents() {
myText = new JTextArea();
myTextScroll = new JScrollPane(myText);
myTextScroll
.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
myTextScroll
.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
myTextScroll.setMaximumSize(new java.awt.Dimension(HOR_SIZE, VER_SIZE));
myTextScroll.setMinimumSize(new java.awt.Dimension(HOR_SIZE, VER_SIZE));
myTextScroll
.setPreferredSize(new java.awt.Dimension(HOR_SIZE, VER_SIZE));
myText.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyTyped(java.awt.event.KeyEvent evt) {
textTyped(evt);
}
});
frame.getContentPane().add(myTextScroll, java.awt.BorderLayout.NORTH);
TAUinDispMsg = new JTextArea();
TAUinDispMsgScroll = new JScrollPane(TAUinDispMsg);
TAUinDispMsg.setBackground(new java.awt.Color(200, 200, 200));
TAUinDispMsgScroll
.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
TAUinDispMsgScroll
.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
TAUinDispMsgScroll.setMaximumSize(new java.awt.Dimension(HOR_SIZE,
VER_SIZE));
TAUinDispMsgScroll.setMinimumSize(new java.awt.Dimension(HOR_SIZE,
VER_SIZE));
TAUinDispMsgScroll.setPreferredSize(new java.awt.Dimension(HOR_SIZE,
VER_SIZE));
TAUinDispMsg.setEditable(false);
frame.getContentPane().add(TAUinDispMsgScroll,
java.awt.BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
private void textTyped(java.awt.event.KeyEvent evt) {
try {
remomsg = new MessageImpl();
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
char c = evt.getKeyChar();
if (c == '\n') {
try {
if (firstMessage) {
name = textString;
// .join(name);
firstMessage = false;
} else {
remomsg.sendMessage(name, textString);
}
} catch (RemoteException ie) {
TAUinDispMsg.append("Failed to send message.");
System.err.println(ie.getMessage());
}
textString = "";
} else {
textString = textString + c;
}
}
@Override
public void updateClients(final String msg) throws RemoteException {
// TODO Auto-generated method stub
System.out.println("Recived Message: " + msg);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
TAUinDispMsg.append(name + " says: " + msg + "\n");
}
});
}
public static void main(String args[]) throws RemoteException {
ChatClient1 ch = null;
try {
ch = new ChatClient1();
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
**ICallback.java: interface for callbacks from server to client**
import java.rmi.*;
public interface ICallback extends Remote {
void updateClients(String msg) throws RemoteException;
}
我想作为业务逻辑（游戏逻辑）的对象。
import java.rmi.*;
public interface Message extends Remote {
public void sendMessage(String name, String message) throws RemoteException;
public void updateClients() throws RemoteException;
}
它的实现：
import java.io.Serializable;
import java.rmi.*;
import java.rmi.server.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class MessageImpl extends UnicastRemoteObject implements Message {
private String name;
private String message;
public MessageImpl() throws RemoteException {
super();
}
public MessageImpl(ArrayList clients2) throws RemoteException {
// TODO Auto-generated constructor stub
this.clients = clients2;
}
static ServerServicesImpl si;
// static ArrayListDemo az;
private List<ICallback> clients = new ArrayList<ICallback>();
// private List<ICallback> clients;
private ServerEngine serverEngine = new ServerEngine();
// Notice this one not called remotely
public void setName(String name) throws RemoteException {
this.name = name;
}
public String getName() {
return name;
}
public void setServerList(ServerEngine serverList2) throws RemoteException {
this.serverEngine = serverList2;
}
public void setClientList(List<ICallback> aclients) throws RemoteException {
this.clients = (ArrayList<ICallback>) aclients;
System.err.println("in setClientlist");
}
public ServerEngine getServerList() {
return serverEngine;
}
// Notice this one not called remotely
public void setMessage(String message) throws RemoteException {
this.message = message;
}
public String getMessage() {
return message;
}
public void updateClients() throws RemoteException {
si = new ServerServicesImpl();
ArrayList j = si.getClientNames();
System.out.println(j.size());
if (clients != null) {
System.out.println(clients.size());
for (ICallback aClient : clients) {
aClient.updateClients(message);
}
} else
System.err.println("Clientlist is empty");
if (clients != null) {
System.out.println(j.size());
} else
System.err.println("Clientlist is empty");
}
public void sendMessage(String name, String message1)
throws RemoteException {
setName(name);
setMessage(message1);
updateClients();
}
}
管理客户端线程的类
import java.lang.*;
import java.util.*;
class ServerEngine {
private Collection<ICallback> threadList =
new ArrayList<ICallback>();
private int counter = 0;
// Get the lock on threadList, and wait until the counter is zero - that
//is, no reads are taking place. Then it's safe to add the thread.
public synchronized void add(ICallback item) {
try {
while (counter > 0) {
wait();
}
threadList.add(item);
}
catch (InterruptedException e) {
System.out.println("Addition interrupted.");
}
finally{
notifyAll();
}
}
// Similarly for removal.
public synchronized void remove(ICallback item) {
try {
while (counter > 0) {
wait();
}
threadList.remove(item);
}
catch (InterruptedException e) {
System.out.println("Removal interrupted.");
}
finally {
notifyAll();
}
}
// Similarly for changing counter
public synchronized void incCounter() {
counter++;
notifyAll();
}
public synchronized void decCounter() {
counter--;
notifyAll();
}
//This is because it would be too much effort to make this class implement
//Collection, return it's own Iterator etc. etc...\
//Note it is *not* a bug that it isn't synchronized
public Collection getCollection() {
return threadList;
}
}
Service.java：服务器将要注册和绑定的对象。
import java.rmi.*;
import java.util.ArrayList;
public interface ServerServices extends Remote {
// added so client can register self with server for callbacks
public void register(ICallback newClient) throws RemoteException;
public ArrayList getClients() throws RemoteException;
}
ServerServicesImpl.java：服务器的实现端
import java.io.Serializable;
import java.rmi.*;
import java.rmi.server.*;
import java.util.*;
class ServerServicesImpl extends UnicastRemoteObject implements ServerServices,
Serializable {
String message;
MessageImpl msgimpl;
static Vector data = new Vector();
private static ArrayList Aclients = new ArrayList<ICallback>();
private static ArrayList testlist;
public ServerServicesImpl() throws RemoteException {
super();
testlist = new ArrayList();
}
public synchronized void register(ICallback newClient)
throws RemoteException {
data.addElement(newClient);
Aclients.add(newClient);
// //serverEngine.add(newClient);
testlist.add("testing");
System.out.println("testlist size =" + testlist.size());
System.out.println(Aclients.size());
setClientList(Aclients);
}
ArrayList getClientNames() {
// Aclients.add(ic);
System.out.println("vector size =" + data.size());
System.out.println("testlist size =" + testlist.size());
System.out.println(" Aclientlist size =" + Aclients.size());
return Aclients;
}
public void setClientList(ArrayList aclients2) {
this.Aclients = aclients2;
}
}
// the server which will publish the above remote object
import java.net.MalformedURLException;
import java.rmi.*;
public class ServiceLoader
{
public static void main(String[] args)
{
try
{
// Install a security manager
System.setSecurityManager(new RMISecurityManager());
ServerServicesImpl obj = new ServerServicesImpl();
Naming.rebind("ChatServer", obj);
System.out.println("ServiceLoader running.");
}
catch (MalformedURLException e)
{
System.err.println(e.getMessage());
}
catch (RemoteException e)
{
System.err.println(e.getMessage());
}
}
}
【问题讨论】：
-
你不应该只粘贴一堆代码，你也应该使用堆栈跟踪发布实际错误。
-
好吧，没有人可以责怪您没有提供所有代码。但是，我有一种奇怪的感觉，即根据您发布的代码量，您将获得的只是 TLDR 帖子。您能否尝试将错误追溯到几个组件？
-
顺便说一句，快速谷歌搜索表明这些类似乎是（至少部分）从uwplatt.edu/csse/tools/java/samples 在线提供的一些 Java RMI 示例复制粘贴。我并不是说这很重要，因为这会使问题无效，但它确实让人怀疑发帖者是否理解他试图使用的代码。
-
我在论坛上是全新的，这实际上是我的第一个论坛，所以有点同情，我不知道哪些事情可能会冒犯人们......
-
提取更少的代码sn-p有利于观众拍bug；您可以在摘录期间了解更多信息：)
标签： java debugging distributed rmi pass-by-reference