Exponential Backoff 자바(안드로이드)소스

import com.google.api.client.http.HttpResponseException;

import com.google.api.services.drive.Drive;
import com.google.api.services.drive.model.File;

import java.io.IOException;
import java.util.Random;
// ...

public class MyClass {
  // ...

  /**
    * Print a file's metadata with exponential backoff.
    *
    * @param service Drive API service instance.
    * @param fileId ID of the file to print metadata for.
    * @return The file's metadata.
    */
  static File printFileWithExponentialBackoff(Drive service, String fileId) throws IOException, InterruptedException {
    Random randomGenerator = new Random();
    for (int n = 0; n < 5; ++n) {
      try {
        File file = service.files().get(fileId).execute();

        System.out.println("Title: " + file.getTitle());
        System.out.println("Description: " + file.getDescription());
        System.out.println("MIME type: " + file.getMimeType());
        return file;
      } catch (GoogleJsonResponseException e) {
        if (e.getCode() == 403
            && (e.getErrors().get(0).getReason().equals("rateLimitExceeded")
                || e.getErrors().get(0).getReason().equals("userRateLimitExceeded"))) {
          // Apply exponential backoff.
          Thread.sleep((1 << n) * 1000 + randomGenerator.nextInt(1001));
        } else {
          // Other error, re-throw.
          throw e;
        }
      }
    }
    System.err.println("There has been an error, the request never succeeded.");
    return null;
  }

  // ...
}

https://developers.google.com/drive/web/handle-errors#implementing_exponential_backoff

public enum Results {
    SUCCESS, 
    NOT_READY, 
    THROTTLED, 
    SERVER_ERROR
}

/*
 * Performs an asynchronous operation, then polls for the result of the
 * operation using an incremental delay.
 */
public static void doOperationAndWaitForResult() {

    try {
        // Do some asynchronous operation.
        long token = asyncOperation();

        int retries = 0;
        boolean retry = false;

        do {
            long waitTime = Math.min(getWaitTimeExp(retries), MAX_WAIT_INTERVAL);

            System.out.print(waitTime + "\n");

            // Wait for the result.
            Thread.sleep(waitTime);

            // Get the result of the asynchronous operation.
            Results result = getAsyncOperationResult(token);

            if (Results.SUCCESS == result) {
                retry = false;
            } else if (Results.NOT_READY == result) {
                retry = true;
            } else if (Results.THROTTLED == result) {
                retry = true;
            } else if (Results.SERVER_ERROR == result) {
                retry = true;
            }
            else {
                // Some other error occurred, so stop calling the API.
                retry = false;
            }

        } while (retry && (retries++ < MAX_RETRIES));
    }

    catch (Exception ex) {
    }
}

/*
 * Returns the next wait interval, in milliseconds, using an exponential
 * backoff algorithm.
 */
public static long getWaitTimeExp(int retryCount) {

    long waitTime = ((long) Math.pow(2, retryCount) * 100L);

    return waitTime;
}

http://docs.aws.amazon.com/general/latest/gr/api-retries.html