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();
/**
* Set the alive time in ms.
*
* @param memberAliveTime the value to set
*/
void setMemberAliveTime(long memberAliveTime);
/**
* The current state of the member.
*
* @return {@code true} if the member is functioning correctly
*/
boolean isReady();
/**
* The current state of the member.
*
* @return {@code true} if the member is suspect, but the crash has not been confirmed
*/
boolean isSuspect();
/**
* @return {@code 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();
/**
* @return the payload associated with this member
*/
byte[] getPayload();
/**
* Set the payload associated with this member.
*
* @param payload the payload
*/
void setPayload(byte[] payload);
/**
* @return the command associated with this member
*/
byte[] getCommand();
/**
* Set the command associated with this member.
*
* @param command the command
*/
void setCommand(byte[] command);
/**
* @return the domain for this cluster
*/
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 {@code true} if the member is local member
*/
boolean isLocal();
/**
* Set if the member is local.
*
* @param local set to {@code true} if this is the local member
*/
void setLocal(boolean local);
}