/** * 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.client; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; import org.apache.hadoop.hbase.HConstants; import java.util.Random; /** * Utility used by client connections such as {@link HConnection} and * {@link ServerCallable} */ @InterfaceAudience.Public @InterfaceStability.Evolving public class ConnectionUtils { private static final Random RANDOM = new Random(); /** * Calculate pause time. * Built on {@link HConstants#RETRY_BACKOFF}. * @param pause * @param tries * @return How long to wait after <code>tries</code> retries */ public static long getPauseTime(final long pause, final int tries) { int ntries = tries; if (ntries >= HConstants.RETRY_BACKOFF.length) { ntries = HConstants.RETRY_BACKOFF.length - 1; } long normalPause = pause * HConstants.RETRY_BACKOFF[ntries]; long jitter = (long)(normalPause * RANDOM.nextFloat() * 0.01f); // 1% possible jitter return normalPause + jitter; } }