/*
* Copyright (c) 2008-2017, Hazelcast, Inc. All Rights Reserved.
*
* Licensed 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 com.hazelcast.nio;
import com.hazelcast.spi.annotation.PrivateApi;
/**
* Responsible for managing {@link com.hazelcast.nio.Connection} objects.
*/
@PrivateApi
public interface ConnectionManager extends ConnectionListenable {
/**
* Gets the number of client connections.
*
* @return number of client connections.
*/
int getCurrentClientConnections();
/**
* Gets the number of text connections (rest/memcache)
*
* @return the number of text connections.
*/
int getAllTextConnections();
/**
* Gets the total number of connections.
*
* @return the total number of connections.
*/
int getConnectionCount();
/**
* Gets the number of active connections.
*
* @return the number of active connections.
*/
int getActiveConnectionCount();
/**
* Gets the connection for a given address. If the connection does not exist, it returns null.
*
* @param address the remote side of the connection.
* @return the found Connection, or none if one doesn't exist.
*/
Connection getConnection(Address address);
/**
* Gets the existing connection for a given address or connects. This call is silent.
*
* @param address the address to connect to.
* @return the found connection, or null if no connection exists.
* @see #getOrConnect(Address, boolean)
*/
Connection getOrConnect(Address address);
/**
* Gets the existing connection for a given address. If it does not exist, the system will try to connect
* asynchronously. In this case, it returns null.
*
* When the connection is established at some point in time, it can be retrieved using the
* {@link #getConnection(Address)}.
*
* @param address the address to connect to.
* @param silent if logging should be done on debug level (silent=true) or on info level (silent=false).
* @return the existing connection.
*/
Connection getOrConnect(Address address, boolean silent);
boolean registerConnection(Address address, Connection connection);
/**
* Deals with cleaning up a closed connection. This method should only be called once by the
* {@link Connection#close(String, Throwable)} method where it is protected against multiple closes.
*/
void onConnectionClose(Connection connection);
/**
* Transmits a packet to a certain connection.
*
* If this method is called with a null connection, the call returns false
*
* @param packet The Packet to transmit.
* @param connection The connection to where the Packet should be transmitted.
* @return true if the transmit was a success, false if a failure. There is no guarantee that the packet is actually going
* to be received since the Packet perhaps is stuck in some buffer. It just means that it is buffered somewhere.
* @throws NullPointerException if packet is null.
*/
boolean transmit(Packet packet, Connection connection);
/**
* Transmits a packet to a certain address.
*
* If the connection to the target doesn't exist yet, the system will try to make the connection. In this case
* true can be returned, even though the connection eventually can't be established.
*
* @param packet The Packet to transmit.
* @param target The address of the target machine where the Packet should be transmitted.
* @return true if the transmit was a success, false if a failure.
* @throws NullPointerException if packet or target is null.
* @see #transmit(com.hazelcast.nio.Packet, com.hazelcast.nio.Connection)
*/
boolean transmit(Packet packet, Address target);
/**
* Starts ConnectionManager, initializes its resources, starts threads, etc. After start, ConnectionManager
* becomes fully operational.
* <p/>
* If it is already started, then this method has no effect.
*
* @throws IllegalStateException if ConnectionManager is shutdown
*/
void start();
/**
* Stops ConnectionManager, releases its resources, stops threads, etc. When stopped, ConnectionManager
* can be started again using {@link #start()}.
* <p/>
* This method has no effect if it is already stopped or shutdown.
* <p/>
* Currently <tt>stop</tt> is called during the merge process to detach node from the current cluster. After
* node becomes ready to join to the new cluster, <tt>start</tt> is called to re-initialize the ConnectionManager.
*/
void stop();
/**
* Shutdowns ConnectionManager completely. ConnectionManager will not be operational anymore and cannot
* be restarted.
* <p/>
* This method has no effect if it is already shutdown.
*/
void shutdown();
}