001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.ipc; 019 020import java.util.HashMap; 021import java.util.Map; 022import org.apache.hadoop.conf.Configuration; 023import org.apache.hadoop.hbase.net.Address; 024import org.apache.hadoop.hbase.util.EnvironmentEdgeManager; 025import org.apache.yetus.audience.InterfaceAudience; 026import org.slf4j.Logger; 027import org.slf4j.LoggerFactory; 028 029/** 030 * A class to manage a list of servers that failed recently. 031 */ 032@InterfaceAudience.Private 033public class FailedServers { 034 private final Map<Address, Long> failedServers = new HashMap<Address, Long>(); 035 private long latestExpiry = 0; 036 private final int recheckServersTimeout; 037 private static final Logger LOG = LoggerFactory.getLogger(FailedServers.class); 038 039 public FailedServers(Configuration conf) { 040 this.recheckServersTimeout = 041 conf.getInt(RpcClient.FAILED_SERVER_EXPIRY_KEY, RpcClient.FAILED_SERVER_EXPIRY_DEFAULT); 042 } 043 044 /** 045 * Add an address to the list of the failed servers list. 046 */ 047 public synchronized void addToFailedServers(Address address, Throwable throwable) { 048 final long expiry = EnvironmentEdgeManager.currentTime() + recheckServersTimeout; 049 this.failedServers.put(address, expiry); 050 this.latestExpiry = expiry; 051 if (LOG.isDebugEnabled()) { 052 LOG.debug("Added failed server with address " + address + " to list caused by " 053 + throwable.toString()); 054 } 055 } 056 057 /** 058 * Check if the server should be considered as bad. Clean the old entries of the list. 059 * @return true if the server is in the failed servers list 060 */ 061 public synchronized boolean isFailedServer(final Address address) { 062 if (failedServers.isEmpty()) { 063 return false; 064 } 065 final long now = EnvironmentEdgeManager.currentTime(); 066 if (now > this.latestExpiry) { 067 failedServers.clear(); 068 return false; 069 } 070 Long expiry = this.failedServers.get(address); 071 if (expiry == null) { 072 return false; 073 } 074 if (expiry >= now) { 075 return true; 076 } else { 077 this.failedServers.remove(address); 078 } 079 return false; 080 } 081}