我有以下代码，当我可以连接到服务器时，一切正常：
public void getXMLData()
{
if (skipUpdate)
{
skipUpdate=false;
return;
}
skipUpdate=true;
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
int SERVERPORT=0;
try {
SERVERPORT = Integer.parseInt(prefs.getString("pref_key_port_1","Port"));
} catch (NumberFormatException e) {
txtStatus.setText("Invalid Port Number");
return;
}
String SERVERHOST = prefs.getString("pref_key_host_1","127.0.0.1");
String PASSWORD = prefs.getString("pref_key_pass_1", "password");
try {
XMLFetcherTask myXMLFetcherTask = new XMLFetcherTask(SERVERHOST,SERVERPORT,PASSWORD);
myXMLFetcherTask.execute();
} catch (Exception e) {
txtStatus.setText("Error "+e.getMessage());
return;
}
skipUpdate=false;
}
public class XMLFetcherTask extends AsyncTask<Void, Void, Void> {
String dstAddress;
int dstPort;
String response = "";
String password="";
XMLFetcherTask(String addr, int port, String pass){
dstAddress = addr;
dstPort = port;
password=pass;
}
@Override
protected Void doInBackground(Void... arg0) {
Socket socket = null;
try {
socket = new Socket(dstAddress, dstPort);
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream())),
true);
out.println(password);
response="";
BufferedReader input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
while (response.toLowerCase().indexOf("</response>")<0)
{
response+=input.readLine();
}
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
txtStatus.setText("UnknownHostException: " + e.getMessage());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
txtStatus.setText("IOException: " + e.getMessage());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
txtStatus.setText("Exception: " + e.getMessage());
} finally{
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
//txtStatus.setText("Exception Finally: " + e.getMessage());
}
}
return null;
}
@Override
protected void onPostExecute(Void result) {
if( !(response.substring(0,5).equalsIgnoreCase("<resp") || response.substring(0,5).equalsIgnoreCase("<?xml")) ) //!response.substring(0,5).equalsIgnoreCase("<?xml") ||
{
txtStatus.setText("Server response doesn't look XML, please check password: '"+response.substring(0,5)+"'");
} else {
lastXMLData=response;
txtStatus.setText("Resp Len: " + response.length());
skipUpdate=false;
updateFragmentListeners();
}
super.onPostExecute(result);
}
}
现在，当我收到UnknownHostException时，app强制关闭以下堆栈跟踪：
07-29 15:52:08.754 1525-1538/android.process.acore V/BackupServiceBinder﹕ doBackup() invoked
07-29 15:52:08.766 1525-1538/android.process.acore E/DictionaryBackupAgent﹕ Couldn't read from the cursor
07-29 16:29:55.178 1525-1534/android.process.acore E/StrictMode﹕ A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
java.lang.Throwable: Explicit termination method 'close' not called
at dalvik.system.CloseGuard.open(CloseGuard.java:184)
at android.os.ParcelFileDescriptor.<init>(ParcelFileDescriptor.java:180)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:916)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:906)
at android.app.IBackupAgent$Stub.onTransact(IBackupAgent.java:71)
at android.os.Binder.execTransact(Binder.java:446)
07-29 16:29:55.178 1525-1534/android.process.acore E/StrictMode﹕ A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
java.lang.Throwable: Explicit termination method 'close' not called
at dalvik.system.CloseGuard.open(CloseGuard.java:184)
at android.os.ParcelFileDescriptor.<init>(ParcelFileDescriptor.java:180)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:916)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:906)
at android.app.IBackupAgent$Stub.onTransact(IBackupAgent.java:64)
at android.os.Binder.execTransact(Binder.java:446)
07-29 16:29:55.178 1525-1534/android.process.acore E/StrictMode﹕ A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
java.lang.Throwable: Explicit termination method 'close' not called
at dalvik.system.CloseGuard.open(CloseGuard.java:184)
at android.os.ParcelFileDescriptor.<init>(ParcelFileDescriptor.java:180)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:916)
at android.os.ParcelFileDescriptor$1.createFromParcel(ParcelFileDescriptor.java:906)
at android.app.IBackupAgent$Stub.onTransact(IBackupAgent.java:57)
at android.os.Binder.execTransact(Binder.java:446)
我不知道为什么会这样...... 我试图评论hte txtStatus.setText，因为它通常不应该从另一个线程工作，但没有变化。 在带有框架22的Android模拟器和带有框架21的手机上测试。 任何想法都会受到欢迎
答案 0 :(得分：0)
好的，我设法使用线程来代替它，这是最终的代码：
public void getXMLData()
{
if (skipUpdate)
{
skipUpdate=false;
return;
}
skipUpdate=true;
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
int SERVERPORT=0;
try {
SERVERPORT = Integer.parseInt(prefs.getString("pref_key_port_1","Port"));
} catch (NumberFormatException e) {
txtStatus.setText("Invalid Port Number");
return;
}
String SERVERHOST = prefs.getString("pref_key_host_1","127.0.0.1");
String PASSWORD = prefs.getString("pref_key_pass_1", "password");
try {
// XMLFetcherTask myXMLFetcherTask = new XMLFetcherTask(SERVERHOST,SERVERPORT,PASSWORD);
// myXMLFetcherTask.execute();
XMLFetcherTask XMLFetcherTaskThread = new XMLFetcherTask();
XMLFetcherTaskThread.dstAddress=SERVERHOST;
XMLFetcherTaskThread.dstPort=SERVERPORT;
XMLFetcherTaskThread.password=PASSWORD;
Thread cThread = new Thread(XMLFetcherTaskThread);
cThread.start();
} catch (Exception e) {
txtStatus.setText("Error "+e.getMessage());
return;
}
skipUpdate=false;
}
public class XMLFetcherTask implements Runnable {
String dstAddress;
int dstPort;
String response = "";
String password="";
private void setStatusFromThread(final String status)
{
runOnUiThread(new Runnable() {
@Override
public void run() {
setStatus(status);
}
});
}
private void updateListenersThread()
{
runOnUiThread(new Runnable() {
@Override
public void run() {
updateFragmentListeners();
}
});
}
public void run() {
Socket socket = null;
//BufferedReader input = null;
//PrintWriter out = null;
try {
socket = new Socket(dstAddress, dstPort);
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream())),
true);
out.println(password);
response="";
BufferedReader input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
while (response.toLowerCase().indexOf("</response>") < 0) {
response+=input.readLine();
}
if( !(response.substring(0,5).equalsIgnoreCase("<resp") || response.substring(0,5).equalsIgnoreCase("<?xml")) ) //!response.substring(0,5).equalsIgnoreCase("<?xml") ||
{
setStatusFromThread("Server response doesn't look XML, please check password: '" + response.substring(0, 5) + "'");
} else {
lastXMLData=response;
Date dNow = new Date( );
SimpleDateFormat ft = new SimpleDateFormat ("hh:mm:ss");
setStatusFromThread("Last update: " + ft.format(dNow));
skipUpdate=false;
updateListenersThread();
}
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
setStatusFromThread("UnknownHostException: " + e.getMessage());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
setStatusFromThread("IOException: " + e.getMessage());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
setStatusFromThread("Exception: " + e.getMessage());
} finally{
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
//txtStatus.setText("Exception Finally: " + e.getMessage());
} catch (Exception e) {
// TODO Auto-generated catch block
}
}
}
}