/**
* 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.cassandra.gms;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.io.ICompactSerializer;
import org.cliffc.high_scale_lib.NonBlockingHashMap;
/**
* This abstraction represents both the HeartBeatState and the ApplicationState in an EndpointState
* instance. Any state for a given endpoint can be retrieved from this instance.
*/
public class EndpointState
{
protected static Logger logger = LoggerFactory.getLogger(EndpointState.class);
private final static ICompactSerializer<EndpointState> serializer = new EndpointStateSerializer();
private volatile HeartBeatState hbState;
final Map<ApplicationState, VersionedValue> applicationState = new NonBlockingHashMap<ApplicationState, VersionedValue>();
/* fields below do not get serialized */
private volatile long updateTimestamp;
private volatile boolean isAlive;
// whether this endpoint has token associated with it or not. Initially set false for all
// endpoints. After certain time of inactivity, gossiper will examine if this node has a
// token or not and will set this true if token is found. If there is no token, this is a
// fat client and will be removed automatically from gossip.
private volatile boolean hasToken;
public static ICompactSerializer<EndpointState> serializer()
{
return serializer;
}
EndpointState(HeartBeatState initialHbState)
{
hbState = initialHbState;
updateTimestamp = System.currentTimeMillis();
isAlive = true;
hasToken = false;
}
HeartBeatState getHeartBeatState()
{
return hbState;
}
void setHeartBeatState(HeartBeatState newHbState)
{
updateTimestamp();
hbState = newHbState;
}
public VersionedValue getApplicationState(ApplicationState key)
{
return applicationState.get(key);
}
/**
* TODO replace this with operations that don't expose private state
*/
@Deprecated
public Map<ApplicationState, VersionedValue> getApplicationStateMap()
{
return applicationState;
}
void addApplicationState(ApplicationState key, VersionedValue value)
{
applicationState.put(key, value);
}
/* getters and setters */
long getUpdateTimestamp()
{
return updateTimestamp;
}
void updateTimestamp()
{
updateTimestamp = System.currentTimeMillis();
}
public boolean isAlive()
{
return isAlive;
}
void markAlive()
{
isAlive = true;
}
void markDead()
{
isAlive = false;
}
void setHasToken(boolean value)
{
hasToken = value;
}
boolean hasToken()
{
return hasToken;
}
}
class EndpointStateSerializer implements ICompactSerializer<EndpointState>
{
private static Logger logger = LoggerFactory.getLogger(EndpointStateSerializer.class);
public void serialize(EndpointState epState, DataOutputStream dos, int version) throws IOException
{
/* serialize the HeartBeatState */
HeartBeatState hbState = epState.getHeartBeatState();
HeartBeatState.serializer().serialize(hbState, dos, version);
/* serialize the map of ApplicationState objects */
int size = epState.applicationState.size();
dos.writeInt(size);
for (Map.Entry<ApplicationState, VersionedValue> entry : epState.applicationState.entrySet())
{
VersionedValue value = entry.getValue();
if (value != null)
{
dos.writeInt(entry.getKey().ordinal());
VersionedValue.serializer.serialize(value, dos, version);
}
}
}
public EndpointState deserialize(DataInputStream dis, int version) throws IOException
{
HeartBeatState hbState = HeartBeatState.serializer().deserialize(dis, version);
EndpointState epState = new EndpointState(hbState);
int appStateSize = dis.readInt();
for ( int i = 0; i < appStateSize; ++i )
{
if ( dis.available() == 0 )
{
break;
}
int key = dis.readInt();
VersionedValue value = VersionedValue.serializer.deserialize(dis, version);
epState.addApplicationState(Gossiper.STATES[key], value);
}
return epState;
}
}