我正在写一个IRC客户端。与IRC服务器的套接字连接通过服务处理。我已经设法在方向更改期间稳定了有问题的活动的所有UI元素，但是在更改期间，服务维护的套接字在某种程度上被关闭。
以下是我认为相关的代码。如果您需要了解更多信息，请与我们联系。
//This is the Service in question
public class ConnectionService extends Service{
private BlockingQueue<String> MessageQueue;
public final IBinder myBind = new ConnectionBinder();
public class ConnectionBinder extends Binder {
ConnectionService getService() {
return ConnectionService.this;
}
}
private Socket socket;
private BufferedWriter writer;
private BufferedReader reader;
private IRCServer server;
private WifiManager.WifiLock wLock;
private Thread readThread = new Thread(new Runnable() {
@Override
public void run() {
try {
String line;
while ((line = reader.readLine( )) != null) {
if (line.toUpperCase().startsWith("PING ")) {
SendMessage("PONG " + line.substring(5));
}
else
queueMessage(line);
}
}
catch (Exception e) {}
}
});
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if(MessageQueue == null)
MessageQueue = new LinkedBlockingQueue<String>();
return Service.START_STICKY;
}
@Override
public IBinder onBind(Intent arg0) {
return myBind;
}
@Override
public boolean stopService(Intent name) {
try {
socket.close();
wLock.release();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return super.stopService(name);
}
@Override
public void onDestroy()
{//I put this here so I had a breakpoint in place to make sure this wasn't firing instead of stopService
try {
socket.close();
wLock.release();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
super.onDestroy();
}
public void SendMessage(String message)
{
try {
writer.write(message + "\r\n");
writer.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
public String readLine()
{
try {
if(!isConnected())
return null;
else
return MessageQueue.take();
} catch (InterruptedException e) {
return "";
}
}
public boolean ConnectToServer(IRCServer newServer)
{
try {
//create a new message queue (connecting to a new server)
MessageQueue = new LinkedBlockingQueue<String>();
//lock the wifi
WifiManager wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wLock = wifiManager.createWifiLock(WifiManager.WIFI_MODE_FULL, "LockTag");
wLock.acquire();
server = newServer;
//connect to server
socket = new Socket();
socket.setKeepAlive(true);
socket.setSoTimeout(60000);
socket.connect(new InetSocketAddress(server.NAME, Integer.parseInt(server.PORT)), 10000);
writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
//run basic login scripts.
if(server.PASS != "")
SendMessage("PASS " + server.PASS);
//write nickname
SendMessage("NICK " + server.NICK);
//write username login
SendMessage("USER " + server.NICK + " 0 * :Fluffy IRC");
String line;
while ((line = reader.readLine( )) != null) {
if (line.indexOf("004") >= 0) {
// We are now logged in.
break;
}
else if (line.indexOf("433") >= 0) {
//change to alt Nick
if(!server.NICK.equals(server.ALT_NICK) && !server.ALT_NICK.equals(""))
{
server.NICK = server.ALT_NICK;
SendMessage("NICK " + server.NICK);
}
else
{
queueMessage("Nickname already in use");
socket.close();
return false;
}
}
else if (line.toUpperCase().startsWith("PING ")) {
SendMessage("PONG " + line.substring(5));
}
else
{
queueMessage(line);
}
}
//start the reader thread AFTER the primary login!!!
CheckStartReader();
if(server.START_CHANNEL == null || server.START_CHANNEL == "")
{
server.WriteCommand("/join " + server.START_CHANNEL);
}
//we're done here, go home everyone
} catch (NumberFormatException e) {
return false;
} catch (IOException e) {
return false;
}
return true;
}
private void queueMessage(String line) {
try {
MessageQueue.put(line);
} catch (InterruptedException e) {
}
}
public boolean isConnected()
{
return socket.isConnected();
}
public void CheckStartReader()
{
if(this.isConnected() && !readThread.isAlive())
readThread.start();
}
}
//Here are the relevant portions of the hosting Activity that connects to the service
//NOTE: THE FOLLOWING CODE IS PART OF THE ACTIVITY, NOT THE SERVICE
private ConnectionService conn;
private ServiceConnection mConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
conn = ((ConnectionService.ConnectionBinder)service).getService();
Toast.makeText(main_tab_page.this, "Connected", Toast.LENGTH_SHORT)
.show();
synchronized (_serviceConnWait) {
_serviceConnWait.notify();
}
}
@Override
public void onServiceDisconnected(ComponentName name) {
conn = null;
}
};
@Override
protected void onSaveInstanceState(Bundle state){
super.onSaveInstanceState(state);
state.putParcelable("Server", server);
state.putString("Window", CurrentTabWindow.GetName());
unbindService(mConnection);
}
@Override
protected void onDestroy()
{
super.onDestroy();
if(this.isFinishing())
stopService(new Intent(this, ConnectionService.class));
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_tab_page);
localTabHost = (TabHost)findViewById(R.id.tabHostMain);
localTabHost.setup();
localTabHost.setOnTabChangedListener(new tabChange());
_serviceConnWait = new Object();
if(savedInstanceState == null)
{//initial startup, coming from Intent to start
//get server definition
server = (IRCServer)this.getIntent().getParcelableExtra(IRC_WINDOW);
server.addObserver(this);
AddTabView(server);
startService(new Intent(this, ConnectionService.class));
}
else
{
server = (IRCServer)savedInstanceState.getParcelable("Server");
String windowName = savedInstanceState.getString("Window");
//Add Needed Tabs
//Server
if(!(windowName.equals(server.GetName())))
AddTabView(server);
//channels
for(IRCChannel c : server.GetAllChannels())
if(!(windowName.equals(c.GetName())))
AddTabView(c);
//reset each view's text (handled by tabChange)
if(windowName.equals(server.GetName()))
SetCurrentTab(server.NAME);
else
SetCurrentTab(windowName);
ResetMainView(CurrentTabWindow.GetWindowTextSpan());
//Rebind to service
BindToService(new Intent(this, ConnectionService.class));
}
}
@Override
protected void onStart()
{
super.onStart();
final Intent ServiceIntent = new Intent(this, ConnectionService.class);
//check start connection service
final Thread serverConnect = new Thread(new Runnable() {
@Override
public void run() {
if(!BindToService(ServiceIntent))
return;
server.conn = conn;
conn.ConnectToServer(server);
server.StartReader();
if(server.START_CHANNEL != null && !server.START_CHANNEL.equals(""))
{
IRCChannel chan = server.FindChannel(server.START_CHANNEL);
if(chan != null)
{
AddTabView(chan);
}
else
{
server.JoinChannel(server.START_CHANNEL);
chan = server.FindChannel(server.START_CHANNEL);
AddTabView(chan);
}
}
}
});
serverConnect.start();
}
private boolean BindToService(Intent ServiceIntent)
{
int tryCount = 0;
bindService(ServiceIntent, mConnection, Context.BIND_AUTO_CREATE);
while(conn == null && tryCount < 10)
{
tryCount++;
try {
synchronized (_serviceConnWait) {
_serviceConnWait.wait(1500);
}
}
catch (InterruptedException e) {
//do nothing
}
}
return conn != null;
}
我不完全确定我在那里做错了什么。显然有一些我想念的东西，还没有找到，或者甚至没想过要检查。但是，在方向更改后，我的发送命令会给我这条消息并且没有任何反应：
06-04 22:02:27.637: W/System.err(1024): java.net.SocketException: Socket closed
06-04 22:02:27.982: W/System.err(1024): at com.fluffyirc.ConnectionService.SendMessage(ConnectionService.java:90)
我不知道套接字什么时候关闭，或者为什么。
更新
我已经更改了代码，而不是绑定到服务并使用它来启动它，而是在适当的位置调用startService和stopService以及绑定到它，在思想上绑定丢失时服务正在被销毁。这与我改变它之前的工作方式完全一样。套接字在方向改变时仍然关闭，我不明白为什么。
更新： - 代码和说明
我添加了最近为Start / Stop服务和START_STICKY所做的代码更改。我最近还阅读了一篇非常好的文章，解释了方向更改流程如何工作以及为什么将android:configChanges="orientation|screenSize"行添加到清单中并不是一个坏主意。所以这解决了方向问题，但如果我将活动置于后台模式，然后将其恢复到前台，它仍然会做同样的事情。这仍然遵循相同的保存/销毁/创建过程，方向没有该清单行......它仍然关闭我的套接字，我仍然不知道为什么。
我知道它在重新创建过程之前不会关闭套接字...我知道这是因为消息队列将显示应用程序在后台时收到的消息，但是一旦我将其恢复转发它关闭套接字，其他任何东西都不能发送或接收。
答案 0 :(得分：1)
＆＃39;套接字关闭＆＃39;意味着你关闭套接字然后继续使用它。它不是“断开连接”。
你需要在catch块中添加一些东西。永远不要忽略异常。当你看到异常实际上是什么时，你可能会感到惊讶。
NB Socket.isConnected()并未告诉您关于连接状态的任何信息：只知道您是否曾连接过Socket.，所以它返回true。