You can use the retryWhen() operator to add retry logic to any Observable.
The following class contains the retry logic:
RxJava 2.x
public class RetryWithDelay implements Function<Observable<? extends Throwable>, Observable<?>> {
private final int maxRetries;
private final int retryDelayMillis;
private int retryCount;
public RetryWithDelay(final int maxRetries, final int retryDelayMillis) {
this.maxRetries = maxRetries;
this.retryDelayMillis = retryDelayMillis;
this.retryCount = 0;
}
@Override
public Observable<?> apply(final Observable<? extends Throwable> attempts) {
return attempts
.flatMap(new Function<Throwable, Observable<?>>() {
@Override
public Observable<?> apply(final Throwable throwable) {
if (++retryCount < maxRetries) {
// When this Observable calls onNext, the original
// Observable will be retried (i.e. re-subscribed).
return Observable.timer(retryDelayMillis,
TimeUnit.MILLISECONDS);
}
// Max retries hit. Just pass the error along.
return Observable.error(throwable);
}
});
}
}
RxJava 1.x
public class RetryWithDelay implements
Func1<Observable<? extends Throwable>, Observable<?>> {
private final int maxRetries;
private final int retryDelayMillis;
private int retryCount;
public RetryWithDelay(final int maxRetries, final int retryDelayMillis) {
this.maxRetries = maxRetries;
this.retryDelayMillis = retryDelayMillis;
this.retryCount = 0;
}
@Override
public Observable<?> call(Observable<? extends Throwable> attempts) {
return attempts
.flatMap(new Func1<Throwable, Observable<?>>() {
@Override
public Observable<?> call(Throwable throwable) {
if (++retryCount < maxRetries) {
// When this Observable calls onNext, the original
// Observable will be retried (i.e. re-subscribed).
return Observable.timer(retryDelayMillis,
TimeUnit.MILLISECONDS);
}
// Max retries hit. Just pass the error along.
return Observable.error(throwable);
}
});
}
}
Usage:
// Add retry logic to existing observable.
// Retry max of 3 times with a delay of 2 seconds.
observable
.retryWhen(new RetryWithDelay(3, 2000));