IntentService onCreate() called but onHandleIntent() not

Question

I'm starting an IntentService with the following method:

private void startMyService(Data data) {
    Intent intent = new Intent(this, MyService.class);
    intent.putExtra(KEY_DATA, data.toJson());
    startService(intent);
}

The Data class:

public class Data extends ArrayList<MyObject> {

    public Data() {
        super();
    }

    public Data(Collection<MyObject> myObjects) {
        super(myObjects);
    }

    public String toJson() {
        return new Gson().toJson(this);
    }

    public static Data fromJson(String jsonString) {
        return new Gson().fromJson(jsonString, Data.class);
    }
}

The relevant part of the IntentService :

public class MyService extends IntentService {

    private Data data;

    public MyService() {
        super("myServiceName");
    }

    @Override
    public void onCreate() {
        super.onCreate();

        // this gets called properly
        Log.d("myTag", "Service onCreate()");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        // this is not called in case of the bigger dataset
        Log.d("myTag", "Service onHandleIntent()");

        String dataJson = intent.getStringExtra(KEY_DATA);
        data = Data.fromJson(dataJson);

        // doing stuff with data
    }
}

I have 2 test scenarios:

• Data holds 2000 objects
• Data holds 4000 objects

With 2000 objects, the Service runs flawlessly.

With 4000 objects, the onCreate() method of the Service is called and that's it... onHandleIntent() is not called. The app just throws an ANR after a while.

I've tested with both Log.d() calls and breakpoints on the first line of onHandleIntent() , it is not called at all when Data holds 4000 objects.

TransactionTooLargeException is not thrown.

I get no Exception s thrown at all, no idea what's wrong.

What could be the cause of this behaviour?

Answer 1

You may not see the TransactionTooLargeException if you are filtering the logcat. There is a reasonable limit to the amount of data that you can pass in an Intent . 4000 objects serialized to JSON is definitely too mucn! This is the wrong approach. Your application architecture is flawed.

You can simply store the 4000 objects in a static variable so that the Service can get to them without having to serialize them, pass them from Activity to Service , then deserialize them.

Alternatively, you need to serialize the 4000 objects to a file, or use a database to hold the data.