org.apache.hadoop.hbase.ipc.FailedServers.java Source code

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Here is the source code for org.apache.hadoop.hbase.ipc.FailedServers.java

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/**
 * 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.ipc;

import java.net.InetSocketAddress;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.apache.hadoop.hbase.util.Pair;

/**
 * A class to manage a list of servers that failed recently.
 */
@InterfaceAudience.Private
public class FailedServers {
    private final Map<String, Long> failedServers = new HashMap<String, Long>();
    private long latestExpiry = 0;
    private final int recheckServersTimeout;
    private static final Log LOG = LogFactory.getLog(FailedServers.class);

    public FailedServers(Configuration conf) {
        this.recheckServersTimeout = conf.getInt(RpcClient.FAILED_SERVER_EXPIRY_KEY,
                RpcClient.FAILED_SERVER_EXPIRY_DEFAULT);
    }

    /**
     * Add an address to the list of the failed servers list.
     */
    public synchronized void addToFailedServers(InetSocketAddress address, Throwable throwable) {
        final long expiry = EnvironmentEdgeManager.currentTime() + recheckServersTimeout;
        this.failedServers.put(address.toString(), expiry);
        this.latestExpiry = expiry;
        if (LOG.isDebugEnabled()) {
            LOG.debug("Added failed server with address " + address.toString() + " to list caused by "
                    + throwable.toString());
        }
    }

    /**
     * Check if the server should be considered as bad. Clean the old entries of the list.
     *
     * @return true if the server is in the failed servers list
     */
    public synchronized boolean isFailedServer(final InetSocketAddress address) {
        if (failedServers.isEmpty()) {
            return false;
        }
        final long now = EnvironmentEdgeManager.currentTime();
        if (now > this.latestExpiry) {
            failedServers.clear();
            return false;
        }
        String key = address.toString();
        Long expiry = this.failedServers.get(key);
        if (expiry == null) {
            return false;
        }
        if (expiry >= now) {
            return true;
        } else {
            this.failedServers.remove(key);
        }
        return false;
    }
}