@Test
public void startReturnDifferentInstances() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	backOff.setInitialInterval(2000L);
	backOff.setMultiplier(2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	BackOffExecution execution2 = backOff.start();

	assertEquals(2000L, execution.nextBackOff());
	assertEquals(2000L, execution2.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(4000L, execution2.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution2.nextBackOff());
}
 

@Test
public void startReturnDifferentInstances() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	backOff.setInitialInterval(2000L);
	backOff.setMultiplier(2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	BackOffExecution execution2 = backOff.start();

	assertEquals(2000L, execution.nextBackOff());
	assertEquals(2000L, execution2.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(4000L, execution2.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution2.nextBackOff());
}
 

@Test
public void startReturnDifferentInstances() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	backOff.setInitialInterval(2000L);
	backOff.setMultiplier(2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	BackOffExecution execution2 = backOff.start();

	assertEquals(2000l, execution.nextBackOff());
	assertEquals(2000l, execution2.nextBackOff());
	assertEquals(4000l, execution.nextBackOff());
	assertEquals(4000l, execution2.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution2.nextBackOff());
}
 

/**
 * Configure a {@link BackOff} for the after rollback processor, based on the consumer
 * retry properties. If retry is disabled, return a {@link BackOff} that disables
 * retry. Otherwise calculate the {@link ExponentialBackOff#setMaxElapsedTime(long)}
 * so that the {@link BackOff} stops after the configured
 * {@link ExtendedConsumerProperties#getMaxAttempts()}.
 * @param extendedConsumerProperties the properties.
 * @return the backoff.
 */
private BackOff createBackOff(
		final ExtendedConsumerProperties<KafkaConsumerProperties> extendedConsumerProperties) {

	int maxAttempts = extendedConsumerProperties.getMaxAttempts();
	if (maxAttempts < 2) {
		return new FixedBackOff(0L, 0L);
	}
	int initialInterval = extendedConsumerProperties.getBackOffInitialInterval();
	double multiplier = extendedConsumerProperties.getBackOffMultiplier();
	int maxInterval = extendedConsumerProperties.getBackOffMaxInterval();
	ExponentialBackOff backOff = new ExponentialBackOff(initialInterval, multiplier);
	backOff.setMaxInterval(maxInterval);
	long maxElapsed = extendedConsumerProperties.getBackOffInitialInterval();
	double accum = maxElapsed;
	for (int i = 1; i < maxAttempts - 1; i++) {
		accum = accum * multiplier;
		if (accum > maxInterval) {
			accum = maxInterval;
		}
		maxElapsed += accum;
	}
	backOff.setMaxElapsedTime(maxElapsed);
	return backOff;
}
 

public <T> T retry(String description, Callable<T> callable) throws Exception {
  ExponentialBackOff backOff =
      new ExponentialBackOff(
          retryConfiguration.getInitialBackoffMillis(),
          retryConfiguration.getRetryMultiplier());
  backOff.setMaxElapsedTime(retryConfiguration.getMaxBackoffMillis());
  BackOffExecution backOffExec = backOff.start();
  while (true) {
    try {
      return callable.call();
    } catch (Throwable e) {
      long waitTime = backOffExec.nextBackOff();
      if (waitTime == BackOffExecution.STOP) {
        throw e;
      }
      log.warn(description + " failed. Retrying in " + waitTime + "ms", e);
      TimeUnit.MILLISECONDS.sleep(waitTime);
    }
  }
}
 

@Test
public void defaultInstance() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(3000L, execution.nextBackOff());
	assertEquals(4500L, execution.nextBackOff());
}
 

@Test
public void simpleIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals(100L, execution.nextBackOff());
	assertEquals(200L, execution.nextBackOff());
	assertEquals(400L, execution.nextBackOff());
	assertEquals(800L, execution.nextBackOff());
}
 

@Test
public void fixedIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 1.0);
	backOff.setMaxElapsedTime(300L);

	BackOffExecution execution = backOff.start();
	assertEquals(100L, execution.nextBackOff());
	assertEquals(100L, execution.nextBackOff());
	assertEquals(100L, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
}
 

@Test
public void maxIntervalReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxInterval(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff()); // max reached
	assertEquals(4000L, execution.nextBackOff());
}
 

@Test
public void maxAttemptsReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff()); // > 4 sec wait in total
}
 

@Test
public void maxIntervalReachedImmediately() {
	ExponentialBackOff backOff = new ExponentialBackOff(1000L, 2.0);
	backOff.setMaxInterval(50L);

	BackOffExecution execution = backOff.start();
	assertEquals(50L, execution.nextBackOff());
	assertEquals(50L, execution.nextBackOff());
}
 

@Test
public void toStringContent() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals("ExponentialBackOff{currentInterval=n/a, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=2000ms, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=4000ms, multiplier=2.0}", execution.toString());
}
 

@Test
public void defaultInstance() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(3000L, execution.nextBackOff());
	assertEquals(4500L, execution.nextBackOff());
}
 

@Test
public void simpleIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals(100L, execution.nextBackOff());
	assertEquals(200L, execution.nextBackOff());
	assertEquals(400L, execution.nextBackOff());
	assertEquals(800L, execution.nextBackOff());
}
 

@Test
public void fixedIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 1.0);
	backOff.setMaxElapsedTime(300L);

	BackOffExecution execution = backOff.start();
	assertEquals(100L, execution.nextBackOff());
	assertEquals(100L, execution.nextBackOff());
	assertEquals(100L, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
}
 

@Test
public void maxIntervalReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxInterval(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff()); // max reached
	assertEquals(4000L, execution.nextBackOff());
}
 

@Test
public void maxAttemptsReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000L, execution.nextBackOff());
	assertEquals(4000L, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff()); // > 4 sec wait in total
}
 

@Test
public void invalidInterval() {
	ExponentialBackOff backOff = new ExponentialBackOff();

	thrown.expect(IllegalArgumentException.class);
	backOff.setMultiplier(0.9);
}
 

@Test
public void maxIntervalReachedImmediately() {
	ExponentialBackOff backOff = new ExponentialBackOff(1000L, 2.0);
	backOff.setMaxInterval(50L);

	BackOffExecution execution = backOff.start();
	assertEquals(50L, execution.nextBackOff());
	assertEquals(50L, execution.nextBackOff());
}
 

@Test
public void toStringContent() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals("ExponentialBackOff{currentInterval=n/a, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=2000ms, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=4000ms, multiplier=2.0}", execution.toString());
}
 

@Test
public void defaultInstance() {
	ExponentialBackOff backOff = new ExponentialBackOff();
	BackOffExecution execution = backOff.start();
	assertEquals(2000l, execution.nextBackOff());
	assertEquals(3000l, execution.nextBackOff());
	assertEquals(4500l, execution.nextBackOff());
}
 

@Test
public void simpleIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals(100l, execution.nextBackOff());
	assertEquals(200l, execution.nextBackOff());
	assertEquals(400l, execution.nextBackOff());
	assertEquals(800l, execution.nextBackOff());
}
 

@Test
public void fixedIncrease() {
	ExponentialBackOff backOff = new ExponentialBackOff(100L, 1.0);
	backOff.setMaxElapsedTime(300l);

	BackOffExecution execution = backOff.start();
	assertEquals(100l, execution.nextBackOff());
	assertEquals(100l, execution.nextBackOff());
	assertEquals(100l, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff());
}
 

@Test
public void maxIntervalReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxInterval(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000l, execution.nextBackOff());
	assertEquals(4000l, execution.nextBackOff());
	assertEquals(4000l, execution.nextBackOff()); // max reached
	assertEquals(4000l, execution.nextBackOff());
}
 

@Test
public void maxAttemptsReached() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	backOff.setMaxElapsedTime(4000L);

	BackOffExecution execution = backOff.start();
	assertEquals(2000l, execution.nextBackOff());
	assertEquals(4000l, execution.nextBackOff());
	assertEquals(BackOffExecution.STOP, execution.nextBackOff()); // > 4 sec wait in total
}
 

@Test
public void invalidInterval() {
	ExponentialBackOff backOff = new ExponentialBackOff();

	thrown.expect(IllegalArgumentException.class);
	backOff.setMultiplier(0.9);
}
 

@Test
public void maxIntervalReachedImmediately() {
	ExponentialBackOff backOff = new ExponentialBackOff(1000L, 2.0);
	backOff.setMaxInterval(50L);

	BackOffExecution execution = backOff.start();
	assertEquals(50L, execution.nextBackOff());
	assertEquals(50L, execution.nextBackOff());
}
 

@Test
public void toStringContent() {
	ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
	BackOffExecution execution = backOff.start();
	assertEquals("ExponentialBackOff{currentInterval=n/a, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=2000ms, multiplier=2.0}", execution.toString());
	execution.nextBackOff();
	assertEquals("ExponentialBackOff{currentInterval=4000ms, multiplier=2.0}", execution.toString());
}
 

@Override
public Response intercept(Chain chain) throws IOException {
  ExponentialBackOff backoff = new ExponentialBackOff();
  backoff.setMaxElapsedTime(maxElapsedBackoffMs);
  BackOffExecution backOffExec = backoff.start();

  Response response = null;
  long waitTime = 0;
  while (waitTime != BackOffExecution.STOP) {
    Request request = chain.request();
    response = chain.proceed(request);
    if (response.isSuccessful()
        || NON_RETRYABLE_METHODS.contains(request.method())
        || response.code() == 404) {
      return response;
    }

    try {
      waitTime = backOffExec.nextBackOff();
      if (waitTime != BackOffExecution.STOP) {
        if (response.body() != null) {
          response.body().close();
        }
        log.warn(
            "Request for "
                + request.url().toString()
                + " failed. Backing off for "
                + waitTime
                + "ms");
        Thread.sleep(waitTime);
      }
    } catch (Throwable ignored) {
      break;
    }
  }
  return response;
}
 

@Override
public void execute() throws CommandException {

    List<String> commandToExecute = getCommandToExecute();

    ExponentialBackOff exponentialBackOff = new ExponentialBackOff(initialInterval, multiplier);
    BackOffExecution backOffExecution = exponentialBackOff.start();

    int numberOfAttempts = 0;
    int exitCode = -1;

    while (exitCode !=0 && numberOfAttempts < maxNumberOfAttempts) {
        try {
            numberOfAttempts++;
            exitCode = executeCommand(commandToExecute);

            if (exitCode != 0) {
                consoleWriter.a("Attempt: ").fg(Ansi.Color.CYAN)
                        .a(numberOfAttempts).a("/").a(maxNumberOfAttempts).reset()
                        .a(" failed. ");
                        
                if (numberOfAttempts < maxNumberOfAttempts) {
                    long nextBackOff = backOffExecution.nextBackOff();
                    consoleWriter.a("Retry in ").fg(Ansi.Color.CYAN).a(nextBackOff / 1000.0).reset().a(" seconds").println();
                    Thread.sleep(nextBackOff);
                } else {
                    consoleWriter.a("Abort").println();
                }
            }
        } catch (CommandException ce) {
            throw ce;
        } catch (Throwable t) {
            throw new CommandException("Couldn't run command with retry", t);
        }
    }

    if (exitCode != 0) {
        throw new CommandWithExitStatusException(exitCode);
    }
}