org.apache.catalina.tribes.Member Maven / Gradle / Ivy
/*
* 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.catalina.tribes;
import java.io.Serializable;
/**
* The Member interface, defines a member in the group.
* Each member can carry a set of properties, defined by the actual implementation.
* A member is identified by the host/ip/uniqueId
* The host is what interface the member is listening to, to receive data
* The port is what port the member is listening to, to receive data
* The uniqueId defines the session id for the member. This is an important feature
* since a member that has crashed and the starts up again on the same port/host is
* not guaranteed to be the same member, so no state transfers will ever be confused
*/
public interface Member extends Serializable {
/**
* When a member leaves the cluster, the payload of the memberDisappeared member
* will be the following bytes. This indicates a soft shutdown, and not a crash
*/
byte[] SHUTDOWN_PAYLOAD = new byte[] {66, 65, 66, 89, 45, 65, 76, 69, 88};
/**
* @return the name of this node, should be unique within the group.
*/
String getName();
/**
* Returns the listen host for the ChannelReceiver implementation
* @return IPv4 or IPv6 representation of the host address this member listens to incoming data
* @see ChannelReceiver
*/
byte[] getHost();
/**
* Returns the listen port for the ChannelReceiver implementation
* @return the listen port for this member, -1 if its not listening on an insecure port
* @see ChannelReceiver
*/
int getPort();
/**
* Returns the secure listen port for the ChannelReceiver implementation.
* Returns -1 if its not listening to a secure port.
* @return the listen port for this member, -1 if its not listening on a secure port
* @see ChannelReceiver
*/
int getSecurePort();
/**
* Returns the UDP port that this member is listening to for UDP messages.
* @return the listen UDP port for this member, -1 if its not listening on a UDP port
*/
int getUdpPort();
/**
* Contains information on how long this member has been online.
* The result is the number of milli seconds this member has been
* broadcasting its membership to the group.
* @return nr of milliseconds since this member started.
*/
long getMemberAliveTime();
void setMemberAliveTime(long memberAliveTime);
/**
* The current state of the member
* @return boolean - true if the member is functioning correctly
*/
boolean isReady();
/**
* The current state of the member
* @return boolean - true if the member is suspect, but the crash has not been confirmed
*/
boolean isSuspect();
/**
* @return boolean - true if the member has been confirmed to malfunction
*/
boolean isFailing();
/**
* returns a UUID unique for this member over all sessions.
* If the member crashes and restarts, the uniqueId will be different.
* @return byte[]
*/
byte[] getUniqueId();
/**
* returns the payload associated with this member
* @return byte[]
*/
byte[] getPayload();
void setPayload(byte[] payload);
/**
* returns the command associated with this member
* @return byte[]
*/
byte[] getCommand();
void setCommand(byte[] command);
/**
* Domain for this cluster
* @return byte[]
*/
byte[] getDomain();
/**
* Highly optimized version of serializing a member into a byte array
* Returns a cached byte[] reference, do not modify this data
* @param getalive calculate memberAlive time
* @return the data as a byte array
*/
byte[] getData(boolean getalive);
/**
* Highly optimized version of serializing a member into a byte array
* Returns a cached byte[] reference, do not modify this data
* @param getalive calculate memberAlive time
* @param reset reset the cached data package, and create a new one
* @return the data as a byte array
*/
byte[] getData(boolean getalive, boolean reset);
/**
* Length of a message obtained by {@link #getData(boolean)} or
* {@link #getData(boolean, boolean)}.
* @return the data length
*/
int getDataLength();
/**
* @return boolean - true if the member is local member
*/
boolean isLocal();
void setLocal(boolean local);
}