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@SeanPONeil
Last active February 15, 2021 21:59
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An extension of the IntentService class that will block an Intent from entering the queue if the same Intent is already in the queue.
package com.atami.mgodroid.util;
import java.util.LinkedList;
import android.app.IntentService;
import android.content.Intent;
/**
* An extension of the IntentService class that will block
* an Intent from entering the queue if the same Intent is
* already in the queue to be run by the Service. A duplicate
* Intent is defined by the filterEqual() method.
* Blocking, for the purpose of this class, means the duplicate
* Intent still resides in IntentService's message queue,
* but onHandleIntent will return quickly after identifying
* the Intent as duplicate.
*
* Note: when using this class, make sure to override
* onHandleBlockingIntent instead of onHandleIntent as you
* would with IntentService.
* @author Sean
*
*/
public abstract class BlockingIntentService extends IntentService {
//Intent Action specifying to do nothing when this
//Action is encountered in onHandleIntent().
protected static String NO_ACTION = "no_action";
//FIFO queue that mimics what is contained in
//IntentService's message queue
private LinkedList<Intent> queue;
public BlockingIntentService(String name) {
super(name);
}
@Override
public void onCreate() {
super.onCreate();
queue = new LinkedList<Intent>();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
for(Intent i: queue){
if(intent.filterEquals(i)){
intent.setAction(NO_ACTION);
break;
}
}
queue.push(intent);
return super.onStartCommand(intent, flags, startId);
}
@Override
protected void onHandleIntent(Intent intent) {
try{
if(!intent.getAction().equals(NO_ACTION)){
onHandleBlockingIntent(intent);
}else{
throw new DuplicateIntentException();
}
}catch(DuplicateIntentException e){
}catch(Exception e){
}finally{
queue.pop();
}
}
protected abstract void onHandleBlockingIntent(Intent intent);
@SuppressWarnings("serial")
public class DuplicateIntentException extends Exception{}
}
@JonasCz
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JonasCz commented Feb 19, 2015

Very handy , thanks.

@dilshaddkhan
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thanks for this post
but my query is after that, when the previous intent get finished how we resume the blocked intent?

@SeanPONeil
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Author

@dilshaddkhan the default IntentService accomplishes what you are asking for.

@dilshaddkhan
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Thank your for the rly,
will you please tell me where should i write my business logic?

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