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Exception in thread "pool-1-thread-1" null pointer Exception NoSuchMethodError

I am working on a multi threaded application where i get some request from JMS, threads are running to receive the message. Here how my thread is working:
Model mapper in the try block is causing the issue i think:
patientAdder.addPatient(patientAddMessage, authResult, queueSender, baseUrl, modelMapper);
here is complete code:
Executors.newSingleThreadExecutor().execute(new Runnable() {
public void run() {
while (true) {
SonicQueueMessageSender queueSender = null;
try {
queueSender = new SonicQueueMessageSender(queueConnProvider);
} catch (JMSException e3) {
// TODO Auto-generated catch block
e3.printStackTrace();
}
String patientAddMessage = null;
try {
patientAddMessage = new SonicMessageReceiver(connectionProvider)
.getAddJsonMessage("MirthMessage");
} catch (JMSException e2) {
// TODO Auto-generated catch block
e2.printStackTrace();
}
final AuthModel auth = new AuthModel();
String authResult = null;
final PatientAdder patientAdder = new PatientAdder();
SecurityTokenModel securityToken = null;
String authPostString = null;
try {
authPostString = new ObjectMapper()
.writeValueAsString(auth);
} catch (JsonGenerationException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Auth post string is: "+ authPostString);
System.out.println("base url is: " + baseUrl);
String authPostOutput = client
.doGetAuthRestPost(authPostString, url);
try {
securityToken = getAuth(authPostOutput);
} catch (JsonParseException 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();
}
authResult = securityToken.getAccessToken();
try {
patientAdder.addPatient(patientAddMessage, authResult, queueSender, baseUrl, modelMapper);
} catch (JsonParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JsonMappingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// poster.postMessage(patientAddMessage, authResult);
catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoSuchMethodException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch(Exception e){
e.printStackTrace();
}
}
}
});
I need to map the message i'm getting in request to a bean class and for that i'm creating a ModelMapper class object that has a function to map properties but when i try to create new object of my mapper class i'm getting a NPE:
Exception in thread "pool-1-thread-1" java.lang.NullPointerException
at com.prnreferral.util.commons.ModelMapper.mapCanonicalMessageToPatientModel(ModelMapper.java:82)
at com.prnreferral.patientprocess.add.PatientAdder.addPatient(PatientAdder.java:52)
at com.prnreferral.patientprocess.add.PIXSAddPatient$1.run(PIXSAddPatient.java:148)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
I'm sure that object is created as i checked it by adding some conditions, but there is something that i'm missing causing this issue
I also tried to add a new function to check if there is any issue with this function, but getting
Exception in thread "pool-1-thread-1" java.lang.NoSuchMethodError: com.prnreferral.util.commons.ModelMapper.printString()V
at com.prnreferral.patientprocess.add.PatientAdder.addPatient(PatientAdder.java:49)
at com.prnreferral.patientprocess.add.PIXSAddPatient$2.run(PIXSAddPatient.java:173)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
I'm stuck on this issue, no idea what to do, can anyone help me. Thanks in advance.

get user groups members using Google Directory API

I'm using the Google Directory API, here is the code that I'm using and I get the user info. But I need to get also the groups that the user is member.
My question is how can I do that when I have the user. I have another code to get the members, from a group but this impractical, because if I do that. I'll will need to get all the members for all the groups.
public static void get_user(String correo) {
Users us;
try {
service = getDirectoryService("admin#domain.mx");
try {
us = service.users().list().setCustomer("my_customer").setQuery("email:"+correo).execute();
System.out.println("us:"+us);
List<User> lu = us.getUsers();
System.out.println("lu:"+lu);
if (lu!=null) {
System.out.println("reses:"+lu.size());
for (int i=0;i<lu.size();i++) {
User u = lu.get(i);
String id = u.getId();
String pemail = u.getPrimaryEmail();
UserName username = u.getName();
System.out.println("xxxx.................");
System.out.println(i+":"+id);
System.out.println("username:"+username.getFullName());
System.out.println("full:"+username.getGivenName());
System.out.println("email:"+pemail);
System.out.println("organization unit:"+u.getOrgUnitPath());
}
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (GeneralSecurityException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (URISyntaxException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}

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.

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

Android app using HttpURLConnection crashes at connect()

I have a following piece of code, basically copy-pasted from examples as I am new to Java and Android (not to programming):
URL vurl = new URL(voteurl); //vuteurl is a string containing a proper URL
HttpURLConnection hc;
hc=null;
hc = (HttpURLConnection)vurl.openConnection();
hc.setRequestMethod("GET");
hc.setDoOutput(true);
hc.setReadTimeout(10000);
hc.connect();
On the line "hc.connect();" the application crashes and Android informs me that it had been stopped.
Adding android.permission.INTERNET to the permisions used by the app did not help.

OK, turns out Android doesn't like network operations in the main thread.
Doing a request in a separate thread does the trick. Thanks guys for Your help!

URL vurl = null;
try {
vurl = new URL(voteurl);
} catch (MalformedURLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} //vuteurl is a string containing a proper URL
HttpURLConnection hc;
hc=null;
try {
hc = (HttpURLConnection)vurl.openConnection();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
hc.setRequestMethod("GET");
} catch (ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
hc.setDoOutput(true);
hc.setReadTimeout(10000);
try {
hc.connect();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}