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Why sendText calls throw timeout exception when using websockets?

I am new to websocket, and trying out with few examples. The application I created works fine for sometime say 10 - 15 mins, and from then on, it throws the timeout exception when sendText method is called on websocket session. I changed the value for "org.apache.tomcat.websocket.BLOCKING_SEND_TIMEOUT" to -1 and now it hangs.
could you please help me to resolve this issue.
The code I have written to send the data to websocket is as below:
public void update() {
Dashboard dashboardData = tunnelDataService.getDashboardData();
ObjectWriter ow = new ObjectMapper().writer();
String json = null;
try {
json = ow.writeValueAsString(dashboardData);
} catch (JsonGenerationException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (JsonMappingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
synchronized (lock) {
if (session.isOpen()) {
session.getBasicRemote().sendText(json);
}
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
I am deploying this application on JBoss EAP 6.3.

Jmock with reflection

I have a requirement where i need to mock the com.sun.deploy.security.DeployManifestChecker and return null when accessing printWarningsIfRequired in that class. Since Deploy.jar is not in my build path, i couldnt directly mock it up. I'm looking at a way to implement it using Java reflection API. but i'm not sure how to invoke the mock method with the Class argument.
method.invoke(null, new Class[]{claz1}); is failing with NP exception.
Here is the code
Mockery context ;
final Class<?> claz1;
try {
Class mclaz = Class.forName("org.jmock.Mockery");
context = (Mockery) mclaz.newInstance();
claz1 = Class.forName("com.sun.deploy.security.DeployManifestChecker");
final Method method = mclaz.getDeclaredMethod("mock",
new Class[]{Class.class} );
method.invoke(null, new Class[]{claz1});
} catch (ClassNotFoundException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoSuchMethodException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

Your stated goal in to use reflection but if I had to do this i'd just create a test-only jar that includes an interface that mimics the com.sun.deploy.security.DeployManifestChecker class. Then use jmock to mock the stand-in.
I've taken this approach before when I couldn't include the actual class in my testing setup like you and it works like a champ. Just be sure that your stand-in doesn't make it to the runtime classpath and remains in test scope only.

Program won't run because variables "may be uninitialized"?

I'm trying to make a new thread for parsing xml from an rss feed. When I click run it says there are errors please correct them etc. I have 2 classes in my project. The other class has no errors and this class below has only warnings that a lot of the things in the try/catch statements may be uninitialized. I understand that and figured I should still be able to run the program anyways, I expect them to be initialized and if they're not that's fine I want to know about it. Is this really what's going on or am I missing something? I thought it would compile if something may be uninitialized but its not certainly uninitialized.
public class RssParse extends Thread {
Thread th=new Thread() {
public void run(){
System.out.println("1");
URL iotd;
try {
iotd = new URL("http://www.nasa.gov/rss/image_of_the_day.rss");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("2");
BufferedReader in;
try {
in = new BufferedReader(new InputStreamReader(iotd.openStream()));
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
System.out.println("3");
XmlPullParserFactory factory;
try {
factory = XmlPullParserFactory.newInstance();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
factory.setNamespaceAware(true);
System.out.println("4");
XmlPullParser xpp;
try {
xpp = factory.newPullParser();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("5");
try {
xpp.setInput(in);
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("6");
int eventType;
try {
eventType = xpp.getEventType();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println(eventType+"!!!!!!!!!!!!!!!!");
while(eventType!=XmlPullParser.END_DOCUMENT){
if(eventType==XmlPullParser.START_DOCUMENT){
System.out.println("start");
}
}
try {
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}//method
};//thread
}//class

Look at this try/catch block for example :
URL iotd;
try {
iotd = new URL("http://www.nasa.gov/rss/image_of_the_day.rss");
} catch (MalformedURLException e) {
e.printStackTrace();
}
If iotd = new URL("...") fails, iotd will remain uninitialized.
There are two ways to deal with this :
Assign a default value to iotd, like : URL iotd = null; However, it's bad here because if you use iotd later its value may be null and can throw a NullPointerException.
Stop the execution of your function if something failed instead of just printing the stack trace. For example you can add a return statement in the catch block :
URL iotd;
try {
iotd = new URL("http://www.nasa.gov/rss/image_of_the_day.rss");
} catch (MalformedURLException e) {
e.printStackTrace();
return;
}

All the warnings you are getting are because all your catch blocks are not dealing with the exception at all (just printing the stacktrace to standard out).
Let's see it through an example:
URL iotd;
try {
iotd = new URL("http://www.nasa.gov/rss/image_of_the_day.rss");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
at that snipped you are declaring a iotd variable as a URL but without initializing it (not assigning any value), you do it inside the try block - which isn't wrong by the way. However if for any reason the statement inside the try block throws an exception program flow will go to the catch block leaving the iotd variable with its initial value (unassigned).
So, in that case, execution of the program will continue and when reaching this statement:
in = new BufferedReader(new InputStreamReader(iotd.openStream()));
it will find no value assigned to the iotd variable.
To remove the warning regarding the uninitialized value you can either assign a null value to the variable when declaring it or rethrow another exception inside the catch block, stopping the program flow.
In the other hand, the snippet you posted here is not just one class, it's actually two as you are extending the Thread class and then creating an anonymous one inside its body. Using threads is easier than that in Java, just implement the Runnable interface and then instantiate a new thread from that interface:
public class MyRunnable implements Runnable {
public void run() {
// do stuff
}
}
and then:
new Thread(new MyRunnable()).start();
cheers

you need to initialize the variables above the try catch block, or give them a value in catch or finally block
find updated code here
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
public class RssParse extends Thread {
Thread th=new Thread() {
public void run(){
System.out.println("1");
URL iotd=null;
try {
iotd = new URL("http://www.nasa.gov/rss/image_of_the_day.rss");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("2");
BufferedReader in=null;
try {
in = new BufferedReader(new InputStreamReader(iotd.openStream()));
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
System.out.println("3");
XmlPullParserFactory factory=null;
try {
factory = XmlPullParserFactory.newInstance();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
factory.setNamespaceAware(true);
System.out.println("4");
XmlPullParser xpp=null;
try {
xpp = factory.newPullParser();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("5");
try {
xpp.setInput(in);
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("6");
int eventType=-1; // set to a default value of your choice
try {
eventType = xpp.getEventType();
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println(eventType+"!!!!!!!!!!!!!!!!");
while(eventType!=XmlPullParser.END_DOCUMENT){
if(eventType==XmlPullParser.START_DOCUMENT){
System.out.println("start");
}
}
try {
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}//method
};//thread
}//class

jfilechooser better look?

When I'm using JFileChooser application in my program on Windows 7 it display such window:
But when I run the JWS File Chooser Demo it displays much better window:
Why?

Because the demo doesn't use JFileChooser; it uses javax.jnlp.FileOpenService, which uses the native OS's file dialog. The source code for that demo is here, check it out.

The Oracle Java Web Start app, is actually using the JNLP API instead of Swing's JFileChooser.
Here is a link: http://download.oracle.com/javase/tutorial/deployment/doingMoreWithRIA/jnlpAPI.html

The major difference could be solved by using the native look and feel. See the main() of FileBro for how to do that.

use this code
try
{
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
}
catch (ClassNotFoundException e1)
{
// TODO Auto-generated catch block
e1.printStackTrace();
}
catch (InstantiationException e1)
{
// TODO Auto-generated catch block
e1.printStackTrace();
}
catch (IllegalAccessException e1)
{
// TODO Auto-generated catch block
e1.printStackTrace();
}
catch (UnsupportedLookAndFeelException e1)
{
// TODO Auto-generated catch block
e1.printStackTrace();
}

how can i call a throwable method inside a runnable, for creating a new thread

while trying to create a progressbar in android i came across this problem.
i am following this example : http://developer.android.com/reference/android/widget/ProgressBar.html
my problem is that one of my methods i want to call has to be inside a try and catch
how do i do that inside of a runnable?
Runnable SendThread = new Runnable()
{
try
{
GetAndConvertImagesToPdf();
mProgStatus = 30;
mProgress.setProgress(mProgStatus);
title.setText(R.string.sendingTitle);
}
catch (DocumentException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
};
i get this error:
"Syntax error on token try, delete this token"
how can i resolve this?
thank you

u put the try in the class body its not in any method or block
this is more like it
Runnable SendThread = new Runnable() {
public void run() {
try {
GetAndConvertImagesToPdf();
mProgStatus = 30;
mProgress.setProgress(mProgStatus);
title.setText(R.string.sendingTitle);
}
catch (DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};

Sorry I am not able to answer your question but I have one advice,Try to explore about AsyncTask it will help you to run a background thread and it will let you update your UI thread as well at same time. however good luck for your current question.
link : http://developer.android.com/reference/android/os/AsyncTask.html
Happy Coding!