Retry Task Framework

If you are using Spring, it is very simple using Spring Retry Library.

Now, Spring Retry is an individual library (earlier it was part of Spring Batch) framework.

Step1: Add spring retry dependency.

<dependency>
    <groupId>org.springframework.retry</groupId>
    <artifactId>spring-retry</artifactId>
    <version>1.1.2.RELEASE</version>
</dependency>

Step2: Add @EnableRetry annotation to your class which contains main() method of your application or into any of your @Configuration class .

Step3: Add @Retryable annotation to your method which you want to retry/call again, in case of exceptions.

@Retryable(maxAttempts=5,backoff = @Backoff(delay = 3000))
public void retrySomething() throws Exception{
    logger.info("printSomething{} is called");
    throw new SQLException();
}

This @Retryable annotation will retry/call retrySomething() 5 times (including the 1st failure).

Current thread will wait for 3000 ms or 3 seconds between next retry.

You can use RetriableTasks as outlined in this post: Retrying Operations in Java. You can quite easily change its waiting algorithm if you like.

Sample code:

//creates a task which will retry 3 times with an interval of 5 seconds
RetriableTask r = new RetriableTask(3, 5000, new Callable(){
    public Object call() throws Exception{
        //put your code here
    }
});
r.call();

If you use Spring:

//import the necessary classes
import org.springframework.batch.retry.RetryCallback;
import org.springframework.batch.retry.RetryContext;
import org.springframework.batch.retry.backoff.ExponentialBackOffPolicy;
import org.springframework.batch.retry.policy.SimpleRetryPolicy;
import org.springframework.batch.retry.support.RetryTemplate;
...

// create the retry template
final RetryTemplate template = new RetryTemplate();
template.setRetryPolicy(new SimpleRetryPolicy(5));
final ExponentialBackOffPolicy backOffPolicy = new ExponentialBackOffPolicy();
backOffPolicy.setInitialInterval(1000L);
template.setBackOffPolicy(backOffPolicy);

// execute the operation using the retry template
template.execute(new RetryCallback<Remote>() {
  @Override
  public Remote doWithRetry(final RetryContext context) throws Exception {
    return (Remote) Naming.lookup("rmi://somehost:2106/MyApp");
  }
});

Original blog post