我知道我在日志猫中遇到的异常有一个非常直截了当的名字。我唯一的问题是我无法确定是什么导致了我的异常。我创建了一个 PC-Android 多客户端聊天。
PC 版可与服务器和客户端 100% 配合使用。我实现了从 PC 客户端到 android 客户端和聊天 WORKS 的相同技术。
我得到的唯一问题是，当我与 android 连接时，clientArea（跟踪所有连接的用户）不跟踪其他名称，而是跟踪 android 客户端用户名的倍数。IE。我只使用用户名：Jurko 在 android 上连接，clientArea 将有 2 个人称为 Jurko，而不是只有一个。
日志猫：
10-11 17:19:08.221: ERROR/AndroidRuntime(12379): FATAL EXCEPTION: main
java.lang.ArrayIndexOutOfBoundsException: length=2; index=2
at com.example.JurkoAndroidChat.MyActivity$ServerTask.onProgressUpdate(MyActivity.java:175)
at com.example.JurkoAndroidChat.MyActivity$ServerTask.onProgressUpdate(MyActivity.java:130)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:647)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4895)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:994)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:761)
at dalvik.system.NativeStart.main(Native Method)
安卓客户端：
package com.example.JurkoAndroidChat;
import android.app.Activity;
import android.content.DialogInterface;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.view.View;
import java.net.*;
import java.io.*;
import java.util.*;
public class MyActivity extends Activity {
/**
* Called when the activity is first created.
*/
// Right here, we connecting the components of the main.xml form to code
Button connectButton, disconnectButton, sendButton;
TextView chatArea, clientArea;
EditText messageField, usernameField, ipField;
//Extra variables and sockets
String username, serverIP;
int Port = 5000;
Socket sock;
PrintWriter out;
BufferedReader in;
ArrayList<String> userList = new ArrayList();
Boolean isConnected = false, exceptionCaught = false;
ServerTask serverTask;
@Override
public void onCreate(Bundle savedInstanceState) {
System.out.println("Working?");
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
connectButton = (Button)findViewById(R.id.button);
sendButton = (Button)findViewById(R.id.button1);
disconnectButton = (Button)findViewById(R.id.button2);
chatArea = (TextView)findViewById(R.id.textView2);
clientArea = (TextView)findViewById(R.id.textView3);
messageField = (EditText)findViewById(R.id.editText2);
usernameField = (EditText)findViewById(R.id.editText);
ipField = (EditText)findViewById(R.id.editText1);
connectButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//To change body of implemented methods use File | Settings | File Templates.
if (isConnected == false) {
username = usernameField.getText().toString();
usernameField.setFocusable(false);
usernameField.setClickable(false);
serverIP = ipField.getText().toString();
ipField.setFocusable(false);
ipField.setClickable(false);
serverTask = new ServerTask();
serverTask.execute();
} else if (isConnected == true) {
chatArea.append("You are already connected to the server.\n");
}
}
});
disconnectButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//To change body of implemented methods use File | Settings | File Templates.
String bye = (username + "µ µDisconnect");
try {
out.print(bye);
out.flush();
chatArea.append("Disconnected.\n");
sock.close();
} catch (Exception e) { } // nothing caught so far.
isConnected = false;
usernameField.setFocusable(true);
usernameField.setClickable(true);
usernameField.setFocusableInTouchMode(true);
ipField.setFocusable(true);
ipField.setFocusableInTouchMode(true);
ipField.setClickable(true);
clientArea.setText("");
}
});
sendButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//To change body of implemented methods use File | Settings | File Templates.
String nothing = "";
if ((messageField.getText().toString().equals(nothing))) {
messageField.setText("");
messageField.requestFocus();
} else {
try {
out.println(username + "µ" + messageField.getText().toString() + "µ" + "Chat");
out.flush();
} catch (Exception e) {
Log.e("Error", e.toString());
chatArea.append("Message was not sent.\n" + e);
}
messageField.setText("");
messageField.requestFocus();
}
}
});
}
public class ServerTask extends AsyncTask<Void, Void, Void> {
String[] data;
String stream, done = "Done", connect = "Connect", disconnect = "Disconnect", chat = "Chat";
@Override
protected Void doInBackground(Void... voids) {
try {
Log.i("Asynctask", "doInBackground");
sock = new Socket(serverIP, Port);
out = new PrintWriter(sock.getOutputStream());
in = new BufferedReader(new InputStreamReader(sock.getInputStream()));
out.println(username + "µ" + "has connected." + "µ" + "Connect");
out.flush();
isConnected = true;
} catch (Exception ex) {
exceptionCaught = true;
Log.e("Application", ex.toString());
}
try {
while ((stream = in.readLine()) != null) {
publishProgress();
}
} catch (Exception e) {}
return null;
}
public void writeUsers() {
clientArea.setText("");
Iterator<String> iterator = userList.iterator();
while (iterator.hasNext()) {
String token = iterator.next();
clientArea.append(token + '\n');
}
}
@Override
protected void onProgressUpdate(Void... values) {
data = stream.split("µ");
if (data[2].equals(chat)) {
if (data[1].equals("has connected.") || data[1].equals("has disconnected."))
chatArea.append(data[0] + " " + data[1] + '\n');
else
chatArea.append(data[0] + ": " + data[1] + '\n');
} else if (data[2].equals(connect)) {
userList.add(data[0]);
writeUsers();
} else if (data[2].equals(disconnect)) {
userList.remove(data[0]);
writeUsers();
} else if (data[2].equals(done))
userList.clear();
}
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
if (exceptionCaught == true) {
chatArea.append("Unable to connect to " + serverIP + " at port " + Port + ".\n");
usernameField.setFocusable(true);
usernameField.setClickable(true);
usernameField.setFocusableInTouchMode(true);
ipField.setFocusableInTouchMode(true);
ipField.setFocusable(true);
ipField.setClickable(true);
exceptionCaught = false;
}
//To change body of overridden methods use File | Settings | File Templates.
}
}
}
服务器（在 PC 上）：
/*
* To change this template, choose Tools : Templates
* and open the template in the editor.
*/
/*
* ServerWindow.java
*
* Created on Apr 23, 2011, 4:16:05 PM
*/
import java.io.*;
import java.net.*;
import java.util.*;
/**
*
* @author JurkoGuba
*/
public class ServerWindow extends javax.swing.JFrame {
ArrayList clientOutputStreams;
ArrayList<String> onlineUsers;
public class ClientHandler implements Runnable {
BufferedReader reader;
Socket sock;
PrintWriter client;
public ClientHandler(Socket clientSocket, PrintWriter user) {
// new inputStreamReader and then add it to a BufferedReader
client = user;
try {
sock = clientSocket;
reader = new BufferedReader(new InputStreamReader(sock.getInputStream()));
} // end try
catch (Exception ex) {
outputPane.append("Error beginning StreamReader. \n");
} // end catch
} // end ClientHandler()
public void run() {
String message, connect = "Connect", disconnect = "Disconnect", chat = "Chat" ;
String[] data;
try {
while ((message = reader.readLine()) != null) {
outputPane.append("Received: " + message + "\n");
data = message.split("µ");
if (data[2].equals(connect)) {
tellEveryone((data[0] + "µ" + data[1] + "µ" + chat));
userAdd(data[0]);
} else if (data[2].equals(disconnect)) {
tellEveryone((data[0] + "µhas disconnected." + "µ" + chat));
userRemove(data[0]);
} else if (data[2].equals(chat)) {
tellEveryone(message);
} else {
outputPane.append("No Conditions were met. \n");
}
} // end while
} // end try
catch (Exception ex) {
outputPane.append("Lost a connection. \n");
ex.printStackTrace();
clientOutputStreams.remove(client);
} // end catch
} // end run()
} // end class ClientHandler
/** Creates new form ServerWindow */
public ServerWindow() {
initComponents();
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
outputPane = new javax.swing.JTextArea();
startButton = new javax.swing.JButton();
stopButton = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("House Server");
outputPane.setColumns(20);
outputPane.setEditable(false);
outputPane.setLineWrap(true);
outputPane.setRows(5);
outputPane.setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
jScrollPane1.setViewportView(outputPane);
startButton.setText("Start");
startButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
startButtonActionPerformed(evt);
}
});
stopButton.setText("Stop");
stopButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
stopButtonActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(startButton, javax.swing.GroupLayout.PREFERRED_SIZE, 179, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(stopButton, javax.swing.GroupLayout.DEFAULT_SIZE, 183, Short.MAX_VALUE))
.addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 380, Short.MAX_VALUE))
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 229, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(startButton)
.addComponent(stopButton))
.addContainerGap(19, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void startButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
Thread starter = new Thread(new ServerStart());
starter.start();
outputPane.append("Server started. \n");
}
private void stopButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
tellEveryone("Serverµis stopping and all users will be disconnected.\nµChat");
outputPane.append("Server stopping... \n");
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new ServerWindow().setVisible(true);
}
});
}
public class ServerStart implements Runnable {
public void run() {
clientOutputStreams = new ArrayList();
onlineUsers = new ArrayList();
try {
ServerSocket serverSock = new ServerSocket(5000);
while (true) {
// set up the server writer function and then begin at the same
// the listener using the Runnable and Thread
Socket clientSock = serverSock.accept();
PrintWriter writer = new PrintWriter(clientSock.getOutputStream());
clientOutputStreams.add(writer);
// use a Runnable to start a 'second main method that will run
// the listener
Thread listener = new Thread(new ClientHandler(clientSock, writer));
listener.start();
outputPane.append("Got a connection. \n");
} // end while
} // end try
catch (Exception ex)
{
outputPane.append("Error making a connection. \n");
} // end catch
} // end go()
}
public void userAdd (String data) {
String add = "µ µConnect", done = "Serverµ µDone", name = data;
outputPane.append("Before " + name + " added. \n");
onlineUsers.add(name);
outputPane.append("After " + name + " added. \n");
tellEveryone(done);
Iterator<String> iterator = onlineUsers.iterator();
while (iterator.hasNext()){
String token = iterator.next();
tellEveryone(token + add);
}
}
public void userRemove (String user) {
String add = "µ µDisconnect", done = "Serverµ µDone";
// Iterator<String> remove = onlineUsers.iterator();
// while (remove.hasNext()) {
// String token = remove.next();
// if (token.equals(user))
// onlineUsers.remove(token);
// }
onlineUsers.remove(user);
tellEveryone(user + add);
}
public void tellEveryone(String message) {
// sends message to everyone connected to server
Iterator it = clientOutputStreams.iterator();
while (it.hasNext()) {
try {
PrintWriter writer = (PrintWriter) it.next();
writer.println(message);
outputPane.append("Sending: " + message + "\n");
writer.flush();
outputPane.setCaretPosition(outputPane.getDocument().getLength());
} // end try
catch (Exception ex) {
outputPane.append("Error telling everyone. \n");
} // end catch
} // end while
} // end tellEveryone()
// Variables declaration - do not modify
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextArea outputPane;
private javax.swing.JButton startButton;
private javax.swing.JButton stopButton;
// End of variables declaration
}