Java tutorial
/* * Druid - a distributed column store. * Copyright 2012 - 2015 Metamarkets Group Inc. * * Licensed 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 io.druid.indexing.common; import com.metamx.emitter.EmittingLogger; import org.joda.time.Duration; /** */ public class RetryPolicy { private static final EmittingLogger log = new EmittingLogger(RetryPolicy.class); private final long maxNumRetries; private final Duration maxRetryDelay; private volatile Duration currRetryDelay; private volatile int retryCount; public RetryPolicy(RetryPolicyConfig config) { this.maxNumRetries = config.getMaxRetryCount(); this.maxRetryDelay = config.getMaxWait().toStandardDuration(); this.currRetryDelay = config.getMinWait().toStandardDuration(); this.retryCount = 0; } public Duration getAndIncrementRetryDelay() { if (hasExceededRetryThreshold()) { return null; } Duration retVal = currRetryDelay; currRetryDelay = new Duration(Math.min(currRetryDelay.getMillis() * 2, maxRetryDelay.getMillis())); ++retryCount; return retVal; } public boolean hasExceededRetryThreshold() { return retryCount >= maxNumRetries; } }