com.hazelcast.nio.Connection Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2018, 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.internal.networking.OutboundFrame;
import com.hazelcast.spi.annotation.PrivateApi;
import java.net.InetAddress;
import java.net.InetSocketAddress;
/**
* Represents a 'connection' between two machines. The most important implementation is the
* {@link com.hazelcast.nio.tcp.TcpIpConnection}.
*/
@PrivateApi
public interface Connection {
/**
* Checks if the Connection is alive.
*
* @return true if alive, false otherwise.
*/
boolean isAlive();
/**
* Returns the clock time in milliseconds of the most recent read using this connection.
*
* @return the clock time of the most recent read
*/
long lastReadTimeMillis();
/**
* Returns the clock time in milliseconds of the most recent write using this connection.
*
* @return the clock time of the most recent write.
*/
long lastWriteTimeMillis();
/**
* Returns the {@link ConnectionType} of this Connection.
*
* @return the ConnectionType. It could be that null is returned.
*/
ConnectionType getType();
/**
* Sets the type of the connection
*
* @param type to be set
*/
void setType(ConnectionType type);
/**
* Checks if it is a client connection.
*
* @return true if client connection, false otherwise.
*/
boolean isClient();
/**
* Returns remote address of this Connection.
*
* @return the remote address. The returned value could be null if the connection is not alive.
*/
InetAddress getInetAddress();
/**
* Returns the address of the endpoint this Connection is connected to, or
* null if it is unconnected.
*
* @return address of the endpoint.
*
* todo: do we really need this method because we have getInetAddress, InetSocketAddress and getEndPoint.
*/
InetSocketAddress getRemoteSocketAddress();
/**
* Gets the {@link Address} of the other side of this Connection.
*
* todo: rename to get remoteAddress?
*
* @return the Address.
*/
Address getEndPoint();
/**
* The remote port.
*
* todo: rename to getRemotePort? And do we need it because we already have getEndPoint which returns an address
* which includes port. It is only used in testing
*
* @return the remote port number to which this Connection is connected, or
* 0 if the socket is not connected yet.
*/
int getPort();
/**
* Writes a outbound frame so it can be received by the other side of the connection. No guarantees are
* made that the frame is going to be received on the other side.
*
* The frame could be stored in an internal queue before it actually is written, so this call
* does not need to be a synchronous call.
*
* @param frame the frame to write.
* @return false if the frame was not accepted to be written, e.g. because the Connection was not alive.
* @throws NullPointerException if frame is null.
*/
boolean write(OutboundFrame frame);
/**
* Closes this connection.
*
* Pending packets on this connection are discarded
*
* If the Connection is already closed, the call is ignored. So it can safely be called multiple times.
*
* @param reason the reason this connection is going to be closed. Is allowed to be null.
* @param cause the Throwable responsible for closing this connection. Is allowed to be null.
*/
void close(String reason, Throwable cause);
/**
* Gets the reason this Connection was closed. Can be null if no reason was given or if the connection is still active. It
* is purely meant for debugging to shed some light on why connections are closed.
*
* This method is thread-safe and can be called at any moment.
*
* If the connection is closed and no reason is available, it is very likely that the close cause does contain the reason
* of closing.
*
* @return the reason this connection was closed.
* @see #getCloseCause()
* @see #close(String, Throwable)
*/
String getCloseReason();
/**
* Gets the cause this Connection was closed. Can be null if no cause was given or if the connection is still active. It
* is purely meant for debugging to shed some light on why connections are closed.
*
* This method is thread-safe and can be called at any moment.
*
* @return the cause of closing this connection.
* @see #getCloseReason() ()
* @see #close(String, Throwable)
*/
Throwable getCloseCause();
}