content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.retry;
  
  import alluxio.util.CommonUtils;
  
  import com.google.common.base.Preconditions;
  
  import javax.annotation.concurrent.NotThreadSafe;
  
  /**
   * A retry policy which allows retrying until a specified timeout is reached.
   */
  @NotThreadSafe
  public class TimeoutRetry implements RetryPolicy {
  
    private final long mRetryTimeoutMs;
    private final long mSleepMs;
    private long mStartMs = 0;
    private int mAttemptCount = 0;
  
    /**
     * Constructs a retry facility which allows retrying until a specified timeout is reached.
     *
     * @param retryTimeoutMs maximum period of time to retry for, in milliseconds
     * @param sleepMs time in milliseconds to sleep before retrying
     */
    public TimeoutRetry(long retryTimeoutMs, long sleepMs) {
      Preconditions.checkArgument(retryTimeoutMs > 0, "Retry timeout must be a positive number");
      Preconditions.checkArgument(sleepMs >= 0, "sleepMs cannot be negative");
      mRetryTimeoutMs = retryTimeoutMs;
      mSleepMs = sleepMs;
    }
  
    @Override
    public int getAttemptCount() {
      return mAttemptCount;
    }
  
    @Override
    public boolean attempt() {
      if (mAttemptCount == 0) {
        // first attempt, set the start time
        mStartMs = CommonUtils.getCurrentMs();
        mAttemptCount++;
        return true;
      }
      if (mSleepMs > 0) {
        CommonUtils.sleepMs(mSleepMs);
      }
      if ((CommonUtils.getCurrentMs() - mStartMs) <= mRetryTimeoutMs) {
        mAttemptCount++;
        return true;
      }
      return false;
    }
  
    @Override
    public RetryPolicy copy() {
      return new TimeoutRetry(mRetryTimeoutMs, mSleepMs);
    }
  }
  