/**
* Copyright 2009 The Apache Software Foundation
*
* 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;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.TreeMap;
import org.apache.hadoop.hbase.master.AssignmentManager.RegionState;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.io.VersionMismatchException;
import org.apache.hadoop.io.VersionedWritable;
/**
* Status information on the HBase cluster.
* <p>
* <tt>ClusterStatus</tt> provides clients with information such as:
* <ul>
* <li>The count and names of region servers in the cluster.</li>
* <li>The count and names of dead region servers in the cluster.</li>
* <li>The name of the active master for the cluster.</li>
* <li>The name(s) of the backup master(s) for the cluster, if they exist.</li>
* <li>The average cluster load.</li>
* <li>The number of regions deployed on the cluster.</li>
* <li>The number of requests since last report.</li>
* <li>Detailed region server loading and resource usage information,
* per server and per region.</li>
* <li>Regions in transition at master</li>
* <li>The unique cluster ID</li>
* </ul>
*/
public class ClusterStatus extends VersionedWritable {
/**
* Version for object serialization. Incremented for changes in serialized
* representation.
* <dl>
* <dt>0</dt> <dd>Initial version</dd>
* <dt>1</dt> <dd>Added cluster ID</dd>
* <dt>2</dt> <dd>Added Map of ServerName to ServerLoad</dd>
* <dt>3</dt> <dd>Added master and backupMasters</dd>
* </dl>
*/
private static final byte VERSION_MASTER_BACKUPMASTERS = 2;
private static final byte VERSION = 2;
private static final String UNKNOWN_SERVERNAME = "unknown";
private String hbaseVersion;
private Map<ServerName, HServerLoad> liveServers;
private Collection<ServerName> deadServers;
private ServerName master;
private Collection<ServerName> backupMasters;
private Map<String, RegionState> intransition;
private String clusterId;
private String[] masterCoprocessors;
/**
* Constructor, for Writable
*/
public ClusterStatus() {
super();
}
public ClusterStatus(final String hbaseVersion, final String clusterid,
final Map<ServerName, HServerLoad> servers,
final Collection<ServerName> deadServers,
final ServerName master,
final Collection<ServerName> backupMasters,
final Map<String, RegionState> rit,
final String[] masterCoprocessors) {
this.hbaseVersion = hbaseVersion;
this.liveServers = servers;
this.deadServers = deadServers;
this.master = master;
this.backupMasters = backupMasters;
this.intransition = rit;
this.clusterId = clusterid;
this.masterCoprocessors = masterCoprocessors;
}
/**
* @return the names of region servers on the dead list
*/
public Collection<ServerName> getDeadServerNames() {
return Collections.unmodifiableCollection(deadServers);
}
/**
* @return the number of region servers in the cluster
*/
public int getServersSize() {
return liveServers.size();
}
/**
* @return the number of dead region servers in the cluster
*/
public int getDeadServers() {
return deadServers.size();
}
/**
* @return the average cluster load
*/
public double getAverageLoad() {
int load = getRegionsCount();
return (double)load / (double)getServersSize();
}
/**
* @return the number of regions deployed on the cluster
*/
public int getRegionsCount() {
int count = 0;
for (Map.Entry<ServerName, HServerLoad> e: this.liveServers.entrySet()) {
count += e.getValue().getNumberOfRegions();
}
return count;
}
/**
* @return the number of requests since last report
*/
public int getRequestsCount() {
int count = 0;
for (Map.Entry<ServerName, HServerLoad> e: this.liveServers.entrySet()) {
count += e.getValue().getNumberOfRequests();
}
return count;
}
/**
* @return the HBase version string as reported by the HMaster
*/
public String getHBaseVersion() {
return hbaseVersion;
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (!(o instanceof ClusterStatus)) {
return false;
}
return (getVersion() == ((ClusterStatus)o).getVersion()) &&
getHBaseVersion().equals(((ClusterStatus)o).getHBaseVersion()) &&
this.liveServers.equals(((ClusterStatus)o).liveServers) &&
this.deadServers.equals(((ClusterStatus)o).deadServers) &&
Arrays.equals(this.masterCoprocessors,
((ClusterStatus)o).masterCoprocessors) &&
this.master.equals(((ClusterStatus)o).master) &&
this.backupMasters.equals(((ClusterStatus)o).backupMasters);
}
/**
* @see java.lang.Object#hashCode()
*/
public int hashCode() {
return VERSION + hbaseVersion.hashCode() + this.liveServers.hashCode() +
this.deadServers.hashCode() + this.master.hashCode() +
this.backupMasters.hashCode();
}
/** @return the object version number */
public byte getVersion() {
return VERSION;
}
//
// Getters
//
/**
* Returns detailed region server information: A list of
* {@link ServerName}.
* @return region server information
* @deprecated Use {@link #getServers()}
*/
public Collection<ServerName> getServerInfo() {
return getServers();
}
public Collection<ServerName> getServers() {
return Collections.unmodifiableCollection(this.liveServers.keySet());
}
/**
* Returns detailed information about the current master {@link ServerName}.
* @return current master information if it exists
*/
public ServerName getMaster() {
return this.master;
}
/**
* @return the number of backup masters in the cluster
*/
public int getBackupMastersSize() {
return this.backupMasters.size();
}
/**
* @return the names of backup masters
*/
public Collection<ServerName> getBackupMasters() {
return Collections.unmodifiableCollection(this.backupMasters);
}
/**
* @param sn
* @return Server's load or null if not found.
*/
public HServerLoad getLoad(final ServerName sn) {
return this.liveServers.get(sn);
}
public Map<String, RegionState> getRegionsInTransition() {
return this.intransition;
}
public String getClusterId() {
return clusterId;
}
public String[] getMasterCoprocessors() {
return masterCoprocessors;
}
//
// Writable
//
public void write(DataOutput out) throws IOException {
super.write(out);
out.writeUTF(hbaseVersion);
out.writeInt(getServersSize());
for (Map.Entry<ServerName, HServerLoad> e: this.liveServers.entrySet()) {
Bytes.writeByteArray(out, e.getKey().getVersionedBytes());
e.getValue().write(out);
}
out.writeInt(deadServers.size());
for (ServerName server: deadServers) {
Bytes.writeByteArray(out, server.getVersionedBytes());
}
out.writeInt(this.intransition.size());
for (Map.Entry<String, RegionState> e: this.intransition.entrySet()) {
out.writeUTF(e.getKey());
e.getValue().write(out);
}
out.writeUTF(clusterId);
out.writeInt(masterCoprocessors.length);
for(String masterCoprocessor: masterCoprocessors) {
out.writeUTF(masterCoprocessor);
}
Bytes.writeByteArray(out, this.master.getVersionedBytes());
out.writeInt(this.backupMasters.size());
for (ServerName backupMaster: this.backupMasters) {
Bytes.writeByteArray(out, backupMaster.getVersionedBytes());
}
}
public void readFields(DataInput in) throws IOException {
int version = getVersion();
try {
super.readFields(in);
} catch (VersionMismatchException e) {
/*
* No API in VersionMismatchException to get the expected and found
* versions. We use the only tool available to us: toString(), whose
* output has a dependency on hadoop-common. Boo.
*/
int startIndex = e.toString().lastIndexOf('v') + 1;
version = Integer.parseInt(e.toString().substring(startIndex));
}
hbaseVersion = in.readUTF();
int count = in.readInt();
this.liveServers = new HashMap<ServerName, HServerLoad>(count);
for (int i = 0; i < count; i++) {
byte [] versionedBytes = Bytes.readByteArray(in);
HServerLoad hsl = new HServerLoad();
hsl.readFields(in);
this.liveServers.put(ServerName.parseVersionedServerName(versionedBytes), hsl);
}
count = in.readInt();
deadServers = new ArrayList<ServerName>(count);
for (int i = 0; i < count; i++) {
deadServers.add(ServerName.parseVersionedServerName(Bytes.readByteArray(in)));
}
count = in.readInt();
this.intransition = new TreeMap<String, RegionState>();
for (int i = 0; i < count; i++) {
String key = in.readUTF();
RegionState regionState = new RegionState();
regionState.readFields(in);
this.intransition.put(key, regionState);
}
this.clusterId = in.readUTF();
int masterCoprocessorsLength = in.readInt();
masterCoprocessors = new String[masterCoprocessorsLength];
for(int i = 0; i < masterCoprocessorsLength; i++) {
masterCoprocessors[i] = in.readUTF();
}
// Only read extra fields for master and backup masters if
// version indicates that we should do so, else use defaults
if (version >= VERSION_MASTER_BACKUPMASTERS) {
this.master = ServerName.parseVersionedServerName(
Bytes.readByteArray(in));
count = in.readInt();
this.backupMasters = new ArrayList<ServerName>(count);
for (int i = 0; i < count; i++) {
this.backupMasters.add(ServerName.parseVersionedServerName(
Bytes.readByteArray(in)));
}
} else {
this.master = new ServerName(UNKNOWN_SERVERNAME, -1,
ServerName.NON_STARTCODE);
this.backupMasters = new ArrayList<ServerName>(0);
}
}
}