I have a webservice on axis2, and in this class a function starts a thread, another function checks if the thread is still running, but when i do a request for the function that checks of the thread is still runnning, i get this error:
org.apache.axis2.AxisFault: Exception occurred while trying to invoke service method isTaskRunning
at org.apache.axis2.util.Utils.getInboundFaultFromMessageContext(Utils.java:531)
at org.apache.axis2.description.OutInAxisOperationClient.handleResponse(OutInAxisOperation.java:375)
at org.apache.axis2.description.OutInAxisOperationClient.send(OutInAxisOperation.java:421)
at org.apache.axis2.description.OutInAxisOperationClient.executeImpl(OutInAxisOperation.java:229)
at org.apache.axis2.client.OperationClient.execute(OperationClient.java:165)
at be.kdg.cosys.thesis.ExecutorStub.isTaskRunning(ExecutorStub.java:487)
at be.kdg.cosys.thesis.AllToPublicScheduler.executeTask(AllToPublicScheduler.java:158)
at be.kdg.cosys.thesis.AllToPublicScheduler.incomingApplication(AllToPublicScheduler.java:106)
at be.kdg.cosys.thesis.ParserToScheduler.run(ParserToScheduler.java:111)
at java.lang.Thread.run(Unknown Source)
Here's is the webservice class:
public class Executor {
private Task task = null;
private long startTime = 0;
private long runTime = 0;
private Thread taskThread=null;
public void execute(byte[] object){
ObjectInputStream in = null;
try {
in = new ObjectInputStream(new ByteArrayInputStream(object));
task = (Task) in.readObject();
in.close();
} catch (IOException | ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
runTime = task.getRunTime();
startTime = System.currentTimeMillis();
taskThread=new Thread(task);
taskThread.start();
}
public long timeToFinish()
{
return runTime-(System.currentTimeMillis()-startTime);
}
public boolean isTaskRunning()
{
return taskThread.isAlive();
}
public byte[] getTask()
{
byte[] ser=null;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutput out = null;
try {
out = new ObjectOutputStream(bos);
out.writeObject(task);
ser = bos.toByteArray();
out.close();
bos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return ser;
}
}
On the server of the webservice i get a nullpointerexeception (log of catalina)
Can anyone help me?
Yorick
Yes you will get a Null pointer exception - Because the Web-service method would not be called on the Same class instance which started the Thread. Since the variable taskThread will be null , and in the method isTaskRunning() calls a method on a null object, it causes a NullpointerException
Ideally , if you need to poll a Thread using web-service , you should use an intimidatory media which states the Status of Thread. intimidatory can be a Database Table which stores the Thread Status
Related
I created a program using threads to read data from file and dispay. Am getting Null pointer exception, first time thread 1 is printing the firstrecord from textfile and second data it removes from file it throws null pointer
public static void main(String[] args) throws InterruptedException, ExecutionException {
ExecutorService es = Executors.newSingleThreadExecutor();
List<String> tasks = getUsersFromFile("new_users.txt");
DoctorDao dao = new DoctorDao();
for (String data : tasks) {
Future<Boolean> result = es.submit(new DoctorTask(data, dao));
while (result.get()) {
System.out.println("data stored!!!");
}
}
es.shutdown();
System.out.println("task done!!!");
}
public static List<String> getUsersFromFile(String fileName) {
List<String> users = new ArrayList<>();
try (BufferedReader reader = new BufferedReader(new FileReader(new File(fileName)))) {
String line = null;
while ((line = reader.readLine()) != null) {
users.add(line);
}
} catch (FileNotFoundException ex) {
// Logger.getLogger(TestExecutors.class.getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
// Logger.getLogger(TestExecutors.class.getName()).log(Level.SEVERE, null, ex);
}
return users;
In Callable implemented class
public Boolean call() throws Exception {
Boolean status = false;
System.out.println(Thread.currentThread().getName() + " processing record for : " + doctorRecord);
StringTokenizer tokenizer = new StringTokenizer(this.doctorRecord, ",");
Doctor doc = null;
while (tokenizer.hasMoreTokens()) {
doc = new Doctor();
doc.setEmailAddress(tokenizer.nextToken());
doc.setName(tokenizer.nextToken());
doc.setId(Integer.valueOf(tokenizer.nextToken()));
status = dao.saveUser(doc);
}
return status;
}
Exception in thread "main" java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at com.executor.demo.readfile.TestDotorExecutor.main(TestDotorExecutor.java:23)
Caused by: java.lang.NullPointerException
at com.executor.demo.readfile.DoctorDao.saveUser(DoctorDao.java:5)
at com.executor.demo.readfile.DoctorTask.call(DoctorTask.java:28)
at com.executor.demo.readfile.DoctorTask.call(DoctorTask.java:1)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
I made a mistake in the code I returned a null value from statiDB class, I didn't intialize List Object, so I modified the code as shown below
This complete code below was missing in above question
In dao class:
public class DoctorDao {
public boolean saveUser(Doctor doc) {
boolean storedStatus = StaticDB.getDoctorList().add(doc);
return storedStatus;
}
}
In DB class
class StaticDB {
static List<Doctor> docList=null;
public static List<Doctor> getDoctorList() {
Doctor doc1 = new Doctor(111,"Shalu","ss#gmail.com");
Doctor doc2 = new Doctor(112,"luke","luke#gmail.com");
docList = new ArrayList<Doctor>(); //This was missing
docList.add(doc1);
docList.add(doc2);
return docList;
}
}
I have a pretty simplistic JavaFX application. In it, I have a Java object for handling database activities, mainly executing queries. To prevent my UI from completely freezing while the query executes, I've implemented a background thread using the javafx.concurrent.Service. This works great on my connect method, which doesn't return anything. However, in my query method it immediately jumps to the return line, and of course returns null. Then it goes back and runs the query, but it's already returned an empty arraylist.
What am I doing wrong?
Here's my method:
public ArrayList<Foo> runQuery() throws SQLException {
ArrayList<Foo> result = new ArrayList<Foo>();
backgroundThread = new Service<Void>() {
#Override
protected Task<Void> createTask() {
return new Task<Void>() {
protected Void call() throws Exception {
stmt = conn.createStatement();
String query = "Select stuff...
rs = stmt.executeQuery(query);
return null;
}
};
}
};
backgroundThread.setOnSucceeded(new EventHandler<WorkerStateEvent>() {
#Override
public void handle(WorkerStateEvent argo) {
try {
while (rs.next()) {
result.add(new Foo(rs.getString(1)));
}
} catch (SQLException e) {
e.printStackTrace();
}
controller.addLogEntry("done.\n");
}
});
backgroundThread.restart();
return result;
}
I am new to JavaFx/Concurrency so I read the tutorial over at Concurrency in JavaFX but I am still a little confused about the implementation of background threads in a JavaFX Gui.
I'm trying to write a small GUI that interfaces with some serial devices (using JSSC-2.8) and that updates the GUI based on the responses from those devices. But, there's a lag between when the message is written and when the device responds, and using Thread.sleep() for an arbitrary amount of time wasn't a reliable way for me program it. So instead I want to use wait() and notify() methods from the concurrency package (with all the appropriate synchronizations), but I am not sure how to implement it. What I initially did is create another Thread, inside the Task, that would write the messages and wait for the responses, and using some bindings, would update the GUI. I've included my code at the end. Here is a short form of the pseudocode I am trying to implement:
start Task:
connect to serial devices
synchronized loop:
send messages
wait() for event to fire
notify()
But what's been happening is, as soon as I call the wait(), the entire application idles and then when notify() is called (after the response fires and event), it doesn't continue where it left off in the recipe() loop, or the startTdk() loop for that matter, it's just idle. Have I implements the threads wrong? When I am calling the wait(), is it a possibility that I cause the EventDispatch or JavaFX Application Thread to pause?
I hope the question is clear, if there are any clarifications needed I can update the post.
public class OmicronRecipe extends Service<String> implements Runnable{
private final String SEPERATOR=";";
private final Tdk tdk;
private final Pvci pvci;
private final SimpleStringProperty data = new SimpleStringProperty("");
private final Float MAX_V = 26.0f,UHV=1e-8f;
private boolean isTdkOn=false, isPvciOn=false;
private String power;
private Float temp,press,maxT, setT;
private int diffMaxT,diffP,diffPow, diffT, index=0;
public OmicronRecipe(){
tdk = new Tdk("COM4");
pvci = new Pvci("COM5");
}
private synchronized void recipe(){
while (true){
try {
sendMessages();
data.set(power+SEPERATOR+temp+SEPERATOR+press);
calcDiffs();
if (diffPow < 0){
if(diffMaxT < 0){
if(diffT < 0){
if (diffP < 0){
if(!rampPow()){
//Max Power reached
}
}else{
//Wait for pressure drop
}
}
}else{
//Wait until quit
}
}else{
//Max power reached
}
Thread.sleep(5000);
} catch (InterruptedException ex) {
Logger.getLogger(OmicronRecipe.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
private synchronized boolean rampPow(){
boolean isRamped=false;
Float setPow = tdk.getSetPow(index), curPow;
setT = tdk.getSetT(index);
curPow = Float.parseFloat(power);
if(curPow.compareTo(setPow) < 0){
do{
curPow += 0.1f;
tdk.sendMessage("PV "+curPow+"\r");
try {
wait();
} catch (InterruptedException ex) {
Logger.getLogger(OmicronRecipe.class.getName()).log(Level.SEVERE, null, ex);
}
curPow = Float.parseFloat(power);
}while(curPow.compareTo(setPow) < 0);
index++;
isRamped=true;
}
return isRamped;
}
public synchronized boolean connect(){
if(!isTdkOn && !isPvciOn){
isTdkOn = tdk.connect();
isPvciOn = pvci.connect();
}
return isTdkOn && isPvciOn;
}
public synchronized boolean disconnect(){
if(tdk!=null && pvci !=null){
isTdkOn = tdk.disconnect();
isPvciOn = pvci.disconnect();
}
return !isTdkOn && !isPvciOn;
}
public synchronized StringProperty getData(){
return data;
}
public void setMaxT(Float maxT){
this.maxT = maxT;
}
private synchronized void calcDiffs(){
Float pow = Float.parseFloat(power);
diffPow = pow.compareTo(MAX_V);
diffMaxT = temp.compareTo(maxT);
diffT = temp.compareTo(100f);
diffP = press.compareTo(UHV);
}
private synchronized void setListeners(){
tdk.getLine().addListener((ov,t, t1)-> {
synchronized (this){
System.out.println("New Power: "+t1);
power = t1;
this.notify();
}
});
pvci.getLine().addListener((ov,t,t1) ->{
synchronized (this){
String[] msg = t1.split(SEPERATOR);
if(msg.length == 2){
switch(msg[0]){
case "temperature":
System.out.println("Temperaute");
temp = Float.parseFloat(msg[1]);
break;
case "pressure":
System.out.println("Pressure");
press = Float.parseFloat(msg[1]);
break;
default:
System.out.println("Nothing; Something went wrong");
break;
}
}
this.notify();
}
});
}
private synchronized void sendMessages(){
try {
tdk.sendMessage("PV?\r");
this.wait();
pvci.sendMessage("temperature");
this.wait();
pvci.sendMessage("pressure");
this.wait();
} catch (InterruptedException ex) {
Logger.getLogger(OmicronRecipe.class.getName()).log(Level.SEVERE, null, ex);
}
}
private synchronized boolean startTdk(){
boolean isOut=false;
if(isTdkOn){
try {
tdk.sendMessage("ADR 06\r");
this.wait();
System.out.println("Power: "+power);
if(power.equals("OK")){
tdk.sendMessage("OUT?\r");
this.wait();
if(power.equals("OFF")){
tdk.sendMessage("OUT ON\r");
this.wait();
isOut = power.equals("ON");
}
else{
isOut = power.equals("ON");
}
}
} catch (InterruptedException ex) {
Logger.getLogger(OmicronRecipe.class.getName()).log(Level.SEVERE, null, ex);
}
}
return isOut;
}
#Override
protected Task<String> createTask() {
return new Task<String>() {
#Override
protected String call() throws IOException{
new Thread(new OmicronRecipe()).start();
return "";
}
};
}
#Override
public void run() {
if (connect()){
setListeners();
if(startTdk()){
recipe();
}
}
}
}
I won't include the Pvci class, because it just a copy of the Tdk class but with specific message sequences to talk with that machine.
public class Tdk {
private SerialPort tdkPort;
private final String portName;
private StringBuilder sb = new StringBuilder("");;
private final StringProperty line = new SimpleStringProperty("");
private final HashMap<Float,Float> calibMap;
private ArrayList<Float> list ;
private boolean isEnd=false;
public Tdk(String portName){
this.portName = portName;
System.out.println("TDK at "+portName);
calibMap = new HashMap();
setMap();
}
public synchronized boolean connect(){
tdkPort = new SerialPort(portName);
try {
System.out.println("Connecting");
tdkPort.openPort();
tdkPort.setParams(9600,
SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
tdkPort.setEventsMask(SerialPort.MASK_RXCHAR);
tdkPort.addEventListener(event -> {
if(event.isRXCHAR()){
if(event.getPortName().equals(portName)){
try {
if(!isEnd){
int[] str = tdkPort.readIntArray();
if(str!=null)
hexToString(str);
}
if(isEnd){
System.out.println("Here: "+sb.toString());
isEnd=false;
String d = sb.toString();
sb = new StringBuilder("");
line.setValue(d);
}
} catch (SerialPortException e) {
Logger.getLogger(Tdk.class.getName()).log(Level.SEVERE, null, e);
}
}
}
});
} catch (SerialPortException e) {
Logger.getLogger(Tdk.class.getName()).log(Level.SEVERE, null, e);
}
return tdkPort !=null && tdkPort.isOpened();
}
public synchronized boolean disconnect(){
if(tdkPort!=null) {
try {
tdkPort.removeEventListener();
if (tdkPort.isOpened())
tdkPort.closePort();
} catch (SerialPortException e) {
Logger.getLogger(Tdk.class.getName()).log(Level.SEVERE, null, e);
}
System.out.println("Disconnecting");
}
return tdkPort.isOpened();
}
public synchronized void sendMessage(String message){
try {
tdkPort.writeBytes(message.getBytes());
} catch (SerialPortException e) {
Logger.getLogger(Tdk.class.getName()).log(Level.SEVERE, null, e);
}
}
private void setMap(){
calibMap.put(1.0f, 25.0f);
calibMap.put(7.0f, 125.0f);
calibMap.put(9.8f, 220.0f);
list = new ArrayList(calibMap.keySet());
}
public Float getSetPow(int index){
return list.get(index);
}
public Float getSetT(int index){
return calibMap.get(list.get(index));
}
public synchronized StringProperty getLine(){
return line;
}
private synchronized void hexToString(int[] hexVal){
for(int i : hexVal){
if(i != 13){
sb.append((char)i);
}else{
isEnd=true;
}
}
System.out.println("Turning: "+Arrays.toString(hexVal)+" to String: "+sb.toString()+" End: "+isEnd);
}
Freeze
Your UI freezes most probably because you are waiting on the FX Apllication Thread, to solve this there are different approaches:
JavaFX Application Thread
You can delegate some work to the FX Application Thread, therefore see Platform.runLater
Not everything can be run on this thread, but for example, in your DeviceController, you can wait until the message appears and then call Platform.runLater() and update the field (you should therefor oc hand the field over to the controller).
DataBinding
What you are describing can also be realised with DataBinding.
With this you could define a SimpleStringProperty, which is bound to your UI Label (.bind() Method). If the controller must fire its message you can set the StringProperty and the UI will update itself.
The scenario you described could be used like this:
start Task:
connect to serial devices
synchronized loop:
send messages
wait() for event to fire
**updateDate the DataBounded fields**
We are taught that, Concurrency notify/wait
Concurrency on level wait()/notify() is very low level. You should try to work with higher level synchronisation methods or helpers (where people have already solved your problems :))
I am pretty new on android and i have problem with asyncTask and threads.
how can i use AsyncTask in this code?
when i using like this productIdList comes null.That's why i want to use AsyncTask. I think using AsyncTask could work.
thanks in advance.
public ArrayList<String> getProductData() {
final ArrayList<String> productIdList = new ArrayList<String>();
new Thread(new Runnable() {
public void run() {
HttpClient httpclient= new DefaultHttpClient();
GeneralConstans GC = new GeneralConstans();
// Products will be stated in memory
HttpPost httpget = new HttpPost(GC.UrlConstants);
HttpResponse response;
String result = null;
try {
HttpContext ctx = new BasicHttpContext();
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(
2);
httpget.setEntity(new UrlEncodedFormEntity(nameValuePairs,
"UTF-8"));
response = httpclient.execute(httpget, ctx);
HttpEntity resEntity = response.getEntity();
if (resEntity != null) {
result = EntityUtils.toString(resEntity);
JSONArray arr = new JSONArray(result);
Gson gson = new Gson();
if (arr.length() > 0) {
for (int j = 0; j < arr.length(); j++) {
Product p = gson.fromJson(arr.getString(j),
Product.class);
productIdList.add(p.toString());
}
}
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (SocketException e) {
/*if (checkAbortStatus(e.getMessage()) == true) {
handler.sendEmptyMessage(0);
}*/
} catch (IOException e) {
/*if (checkAbortStatus(e.getMessage()) == true) {
handler.sendEmptyMessage(0);
}*/
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
}
private Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
}
};
}).start();
return productIdList;
A Async task implicitly moves methods and commands away from the main thread, as the MAIN thread should run all tasks.
create a new class,
public class <NAME OF CLASS> extends AsyncTask<Void, String, String>
the extends part basically extends (inherits in c#) taking in some parameters, these parameters relate to the 3 overrided methods you are going to utilise.
onPreExecute - this is a kind of pre doing things method, i personally dont need it code i've written (i'm still new to android myself)
onDoInBackgound - this is the main part of the AsyncTask, this is where all your method will go, this is where all the logic will happen. This is exactly what it says on the tin, it does everything in the background on the other thread.
onPostExecute - when the onDoInBackground is finished it will run the OnPostExecute method, i usually have a String return on the onDoInBackgroun method, which ensures it progresses to the onPostExecute as i found sometimes without it it didnt quite progress.
then in the postExecute method you tell it what you want to do once all the logic is done, e.g you could have a listener on the Main thread in which you call that listener from the AysncTask i.e listener.onSuccess(results) in the postExecute Method, which will return you to the original thread.
Hope this helps
Hi I am new to android and I am learning by example. I am trying to make an activity that has a list view of all songs in my raw folder with media player controls at the bottom. I have everything working so far but I can't seem to get the SeekBar to stop force closing.
Here is the code:
public class music extends ListActivity implements Runnable {
private ArrayList<sound> mSounds = null;
private soundadapter mAdapter = null;
private ImageButton playbtn;
private SeekBar seekbar;
private int total;
private MediaPlayer mp = null;
private TextView selelctedFile = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.music);
selelctedFile = (TextView) findViewById(R.id.selectedfile);
seekbar = (SeekBar) findViewById(R.id.seekbar);
seekbar.setProgress(0);
// create a simple list
mSounds = new ArrayList<sound>();
sound s = new sound();
s.setDescription("Rudolph The Red Nosed Reindeer");
s.setSoundResourceId(R.raw.rudolphtherednosereindeer);
mSounds.add(s);
s = new sound();
s.setDescription("Battery");
s.setSoundResourceId(R.raw.battery);
mSounds.add(s);
mAdapter = new soundadapter(this, R.layout.listitem, mSounds);
setListAdapter(mAdapter);
playbtn = (ImageButton) findViewById(R.id.play);
playbtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
try {
if (mp.isPlaying()) {
mp.pause();
playbtn.setImageResource(android.R.drawable.ic_media_play);
} else {
mp.start();
playbtn.setImageResource(android.R.drawable.ic_media_pause);
}
} catch (Exception e) {
e.printStackTrace();
// TODO: handle exception
}
}
});
}
#Override
public void onListItemClick(ListView parent, View v, int position, long id) {
sound s = (sound) mSounds.get(position);
if (mp != null) {
mp.reset();
mp.release();
}
mp = MediaPlayer.create(this, s.getSoundResourceId());
selelctedFile.setText(s.getDescription());
playbtn.setImageResource(android.R.drawable.ic_media_pause);
mp.start();
total = mp.getDuration();
seekbar.setMax(total);
seekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
#Override
public void onStopTrackingTouch(SeekBar seekbar) {
// TODO Auto-generated method stub
}
#Override
public void onStartTrackingTouch(SeekBar seekbar) {
// TODO Auto-generated method stub
}
#Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
if (fromUser) {
mp.seekTo(progress);
seekBar.setProgress(progress);
}
}
});
Thread currentThread = new Thread(this);
currentThread.start();
}
#Override
public void run() {
// TODO Auto-generated method stub
try {
while (mp != null) {
int currentPosition = mp.getCurrentPosition();
Message msg = new Message();
msg.what = currentPosition;
threadHandler.sendMessage(msg);
Thread.sleep(100);
}
}
catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
}
}
private Handler threadHandler = new Handler() {
public void handleMessage(Message msg) {
// super.handleMessage(msg);
// txt.setText(Integer.toString(msg.what));
seekbar.setProgress(msg.what);
}
};
#Override
protected void onPause() {
// TODO Auto-generated method stub
mp.stop();
mp.release();
mp = null;
}
#Override
protected void onDestroy() {
// TODO Auto-generated method stub
if(mp != null) {
mp.stop();
mp.release();
mp = null;
}
}
}
and here is the error i keep getting when i click several times on different songs:
04-14 02:53:00.452: W/dalvikvm(27452): threadid=19: thread exiting with uncaught exception (group=0x40018560)
04-14 02:53:00.466: E/AndroidRuntime(27452): FATAL EXCEPTION: Thread-22
04-14 02:53:00.466: E/AndroidRuntime(27452): java.lang.IllegalStateException
04-14 02:53:00.466: E/AndroidRuntime(27452): at android.media.MediaPlayer.getCurrentPosition(Native Method)
04-14 02:53:00.466: E/AndroidRuntime(27452): at net.cybercore.collapsingfromwithin.music.run(music.java:145)
04-14 02:53:00.466: E/AndroidRuntime(27452): at java.lang.Thread.run(Thread.java:1019)
Line error 145 is :
int currentPosition = mp.getCurrentPosition();
I cannot for the life of me figure out why it works for 3 or 4 times playing and then it kills the app.
Any help is appreciated. I have already looked at several other sites for examples including http://www.androidhive.info/2012/03/android-building-audio-player-tutorial/ and http://www.androiddevblog.net/android/playing-audio-in-android
**
UPDATE
**
I think I fixed it. thanks for your help I found Thread using for seekbar on android mediaplayer so i changed it to
#Override
public void run() {
// TODO Auto-generated method stub
try {
while (mp != null) {
int currentPosition = mp.getCurrentPosition();
Message msg = new Message();
msg.what = currentPosition;
threadHandler.sendMessage(msg);
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("interrupt exeption" + e);
}
}
}
catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.out.println("My exeption" + e);
}
}
I still get the errors but they are not killing my app. I don't think this is right way to do it but its working.
You should prepare your media player when instanciating it.
A MediaPlayer object must first enter the Prepared state before playback can be started.
There are two ways (synchronous vs. asynchronous) that the Prepared state can be reached: either a call to prepare() (synchronous) which transfers the object to the Prepared state once the method call returns, or a call to prepareAsync() (asynchronous) which first transfers the object to the Preparing state after the call returns (which occurs almost right way) while the internal player engine continues working on the rest of preparation work until the preparation work completes. When the preparation completes or when prepare() call returns, the internal player engine then calls a user supplied callback method, onPrepared() of the OnPreparedListener interface, if an OnPreparedListener is registered beforehand via setOnPreparedListener(android.media.MediaPlayer.OnPreparedListener).
Read it here
so you should call mp.prepare() after instanciating the player.
also you should make sure the media player in playing to run the run method. I'd start by adding
mp.isPlaying() to the while line.
while (mp != null && mp.isPlaying()) {
...
}
IllegalStateException means that you are on an illegal state to call that method, like for instance, if the player is stopped.
I'm not sure, but I think this will stop the run method when you pause the music. So you should try to avoid this. I create a boolean to identify that the player is playing or paused and use it on the while.