exeption while using JSR82

[manojkumar.m]

Hello every body,

I am developing an application using jsr82. When I call a function to search for services (DiscoveryAgent.searchServices()), I am getting an error like this:

java.lang.NullPointerException
at com.sun.kvem.jsr082.bluetooth.DataL2CAPReaderWriter.<init>(+41).

can any one help me why I am getting this exception.

[Tiger79]

i am having a similar problem, so I awas wondering how did u catch the exception ?

[manojkumar.m]

still the problem remains same. can any one help me please.

[ttsorr]

I would guess that the reason you are not getting any help is that you are not very specific in your question.

Please post the code that throws the exception, including how you acquire the remote device...

best,
mattias

[hartti]

Also tell what device you are seeing this problem on.

Hartti

[manojkumar.m]

Hi Harti,

Thanks for responding. I am getting this error on using WTK25.

[manojkumar.m]

Hello ttsorr,

Here I am giving the code....please check once.

private boolean searchServices() {

state = SERVICE_SEARCH;
records.removeAllElements();
searchIDs = new int[devices.size()];
System.out.println("devices size : " + devices.size());
boolean isSearchStarted = false;

for (int i = 0; i < devices.size(); i++) {
RemoteDevice rd = (RemoteDevice)devices.elementAt(i);
try {
if (attrSet == null)
{
System.out.println("attrSet is null");
}
else
{
System.out.println("attrSet is not null");
}
if (uuidSet == null)
{
System.out.println("uuidSet is null");
}
else
{
System.out.println("uuidSet is not null);
}
if (rd == null)
{
System.out.println("rd is null");
}
else
{
System.out.println("rd is not null"); }
searchIDs[i] = discoveryAgent.searchServices(attrSet, uuidSet, rd, this);
//attrSet = 0x4321;
//uuidSet = 0x1101,F0E0D0C0B0A000908070605040302010
}
catch (Exception e)
{//BluetoothState
System.err.println("Can't search services for: " + rd.getBluetoothAddress() +
" due to " + e);
searchIDs[i] = -1;
e.printStackTrace();
continue;
}


}

// at least one of the services search should be found


return true;
}

try {
wait(); // until services are found
} catch (InterruptedException e) {
System.err.println("Unexpected interruption: " + e);

return false;
}


// actually, no services were found
if (records.size() == 0) { // here records is a vector
System.out.println("No proper services were found");
}

return true;
}

[ttsorr]

What's your attrSet and uuidSet?
Also, some devices dont seem to mind, but many devices complain when you scan multiple devices simultaneusly.

Another way to implement that would be to either implement wait/notify, for each service search, or to start a new service search in serviceSearchCompleted if there are more devices to scan.
I don't know if this is what causes your problems, but it is worth considerations.

rrostt

[rrafols]

That exception in the emulator is strange, but when launching service discover you should not launch more than the number indicated in the 'bluetooth.sd.trans.max' property.

You could get this value using LocalDevice.getLocalDevice().getProperty('bluetooth.sd.trans.max');

Also, you may try with attrSet set to null, so the default attr will be get as stated in the jsr 82 documentation:

The default attributes are ServiceRecordHandle (0x0000), ServiceClassIDList (0x0001), ServiceRecordState (0x0002), ServiceID (0x0003), and ProtocolDescriptorList (0x0004).If attrSet is null then only the default attributes will be retrieved.

[manojkumar.m]

thankyou very much for your reply.
It helped me a lot.

[kamanashisroy]

Hi,

I have the same problem .. I am using WTK 2.5.2 and it is the same NullPointerException at com.sun.kvem.jsr082.bluetooth.DataL2CAPReaderWriter.<init>(+41).

Unfortunately this exception is not catchable(strange !) ..

I did not simultaneously searched services in different devices.

The error does not happen all the time. If I restart every simulation and there bluetooth server available then it works fine.


Finally it is not chatchable ! strange !

[kuras234]

hi,

I have similar problem, when i run 2 (or more) emulators, search device, kill emulator and search. Are you have a idea??
I'm use WTK 2.5.2



java.lang.NullPointerException
at com.sun.kvem.jsr082.bluetooth.DataL2CAPReaderWriter.<init>(DataL2CAPReaderWriter.java:51)
at com.sun.kvem.jsr082.bluetooth.SDPClient$SDPTransport.start(+100)
at com.sun.kvem.jsr082.bluetooth.SDPClient.openTransport(SDPClient.java:103)
at com.sun.kvem.jsr082.bluetooth.SDPClient.open(SDPClient.java:184)
at com.sun.kvem.jsr082.bluetooth.SDPClient.<init>(SDPClient.java:69)
at com.sun.kvem.jsr082.bluetooth.ServiceSearcher.start(ServiceSearcher.java:77)
at com.sun.kvem.jsr082.bluetooth.DiscoveryAgentImpl.searchServices(DiscoveryAgentImpl.java:226)
at javax.bluetooth.DiscoveryAgent.searchServices(DiscoveryAgent.java:259)
at main.BTClient.searchServices(BTClient.java:313)
at main.BTClient.findService(BTClient.java:393)
at main.BTClient.run(BTClient.java:103)
at main.BTTaskManager.doTask(BTTaskManager.java:101)
at main.BTTaskManager.run(BTTaskManager.java:61)

[manjul_saini]

Hello every body,

I am developing an application using jsr82. When I call a function to search for services (DiscoveryAgent.searchServices()), I am getting an error like this:

java.lang.NullPointerException
at com.sun.kvem.jsr082.bluetooth.DataL2CAPReaderWriter.<init>(+41).

can any one help me why I am getting this exception.

Hi, if i am not wrong you are getting error on emulator right? and yeah you will get it, first of all you must be clear that you are searching a service on emulator, so that emulator must provide a service right? other wise it will give a nullptrexe.
So start a server as soon as your application starts, means it should be ready to recieve any message as soon as your app starts.