/**
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.util;
import java.util.concurrent.TimeUnit;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
@InterfaceAudience.Private
public class RetryCounter {
private static final Log LOG = LogFactory.getLog(RetryCounter.class);
private final int maxRetries;
private int retriesRemaining;
private final int retryIntervalMillis;
private final TimeUnit timeUnit;
public RetryCounter(int maxRetries,
int retryIntervalMillis, TimeUnit timeUnit) {
this.maxRetries = maxRetries;
this.retriesRemaining = maxRetries;
this.retryIntervalMillis = retryIntervalMillis;
this.timeUnit = timeUnit;
}
public int getMaxRetries() {
return maxRetries;
}
/**
* Sleep for a exponentially back off time
* @throws InterruptedException
*/
public void sleepUntilNextRetry() throws InterruptedException {
int attempts = getAttemptTimes();
long sleepTime = (long) (retryIntervalMillis * Math.pow(2, attempts));
LOG.info("Sleeping " + sleepTime + "ms before retry #" + attempts + "...");
timeUnit.sleep(sleepTime);
}
public boolean shouldRetry() {
return retriesRemaining > 0;
}
public void useRetry() {
retriesRemaining--;
}
public int getAttemptTimes() {
return maxRetries-retriesRemaining+1;
}
}