javax.websocket.Session Maven / Gradle / Ivy
/*
* Copyright (c) 2018 Oracle and/or its affiliates and others.
* All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package javax.websocket;
import java.io.Closeable;
import java.io.IOException;
import java.net.URI;
import java.security.Principal;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* A Web Socket session represents a conversation between two web socket endpoints. As soon as the websocket handshake
* completes successfully, the web socket implementation provides the endpoint an open websocket session. The endpoint
* can then register interest in incoming messages that are part of this newly created session by providing a
* MessageHandler to the session, and can send messages to the other end of the conversation by means of the
* RemoteEndpoint object obtained from this session.
*
* Once the session is closed, it is no longer valid for use by applications. Calling any of its methods (with the
* exception of the close() methods) once the session has been closed will result in an
* {@link java.lang.IllegalStateException} being thrown. Developers should retrieve any information from the session
* during the {@link Endpoint#onClose} method. Following the convention of {@link java.io.Closeable} calling the Session
* close() methods after the Session has been closed has no effect.
*
* Session objects may be called by multiple threads. Implementations must ensure the integrity of the mutable
* properties of the session under such circumstances.
*
* @author dannycoward
*/
public interface Session extends Closeable {
/**
* Return the container that this session is part of.
*
* @return the container.
*/
WebSocketContainer getContainer();
/**
* Register to handle to incoming messages in this conversation. A maximum of one message handler per native
* websocket message type (text, binary, pong) may be added to each Session. I.e. a maximum of one message handler
* to handle incoming text messages a maximum of one message handler for handling incoming binary messages, and a
* maximum of one for handling incoming pong messages. For further details of which message handlers handle which of
* the native websocket message types please see {@link MessageHandler.Whole} and {@link MessageHandler.Partial}.
* Adding more than one of any one type will result in a runtime exception.
*
* This method is not safe to use unless you are providing an anonymous class derived directly from
* {@link javax.websocket.MessageHandler.Whole} or {@link javax.websocket.MessageHandler.Partial}. In all other
* cases (Lambda Expressions, more complex inheritance or generic type arrangements), one of the following methods
* have to be used: {@link #addMessageHandler(Class, javax.websocket.MessageHandler.Whole)} or
* {@link #addMessageHandler(Class, javax.websocket.MessageHandler.Partial)}.
*
* @param handler the MessageHandler to be added.
* @throws IllegalStateException if there is already a MessageHandler registered for the same native websocket
* message type as this handler.
*/
void addMessageHandler(MessageHandler handler) throws IllegalStateException;
/**
* Register to handle to incoming messages in this conversation. A maximum of one message handler per native
* websocket message type (text, binary, pong) may be added to each Session. I.e. a maximum of one message handler
* to handle incoming text messages a maximum of one message handler for handling incoming binary messages, and a
* maximum of one for handling incoming pong messages. For further details of which message handlers handle which of
* the native websocket message types please see {@link MessageHandler.Whole} and {@link MessageHandler.Partial}.
* Adding more than one of any one type will result in a runtime exception.
*
* @param type of message that the given handler is intended for.
* @param clazz type of the message processed by message handler to be registered.
* @param handler whole message handler to be added.
* @throws IllegalStateException if there is already a MessageHandler registered for the same native websocket
* message type as this handler.
* @since WebSocket 1.1
*/
public void addMessageHandler(Class clazz, MessageHandler.Whole handler);
/**
* Register to handle to incoming messages in this conversation. A maximum of one message handler per native
* websocket message type (text, binary, pong) may be added to each Session. I.e. a maximum of one message handler
* to handle incoming text messages a maximum of one message handler for handling incoming binary messages, and a
* maximum of one for handling incoming pong messages. For further details of which message handlers handle which of
* the native websocket message types please see {@link MessageHandler.Whole} and {@link MessageHandler.Partial}.
* Adding more than one of any one type will result in a runtime exception.
*
* @param type of message that the given handler is intended for.
* @param clazz type of the message processed by message handler to be registered.
* @param handler partial message handler to be added.
* @throws IllegalStateException if there is already a MessageHandler registered for the same native websocket
* message type as this handler.
* @since WebSocket 1.1
*/
public void addMessageHandler(Class clazz, MessageHandler.Partial handler);
/**
* Return an unmodifiable copy of the set of MessageHandlers for this Session.
*
* @return the set of message handlers.
*/
Set getMessageHandlers();
/**
* Remove the given MessageHandler from the set belonging to this session. This method may block if the given
* handler is processing a message until it is no longer in use.
*
* @param handler the handler to be removed.
*/
void removeMessageHandler(MessageHandler handler);
/**
* Returns the version of the websocket protocol currently being used. This is taken as the value of the
* Sec-WebSocket-Version header used in the opening handshake. i.e. "13".
*
* @return the protocol version.
*/
String getProtocolVersion();
/**
* Return the sub protocol agreed during the websocket handshake for this conversation.
*
* @return the negotiated subprotocol, or the empty string if there isn't one.
*/
String getNegotiatedSubprotocol();
/**
* Return the list of extensions currently in use for this conversation.
*
* @return the negotiated extensions.
*/
List getNegotiatedExtensions();
/**
* Return true if and only if the underlying socket is using a secure transport.
*
* @return whether its using a secure transport.
*/
boolean isSecure();
/**
* Return true if and only if the underlying socket is open.
*
* @return whether the session is active.
*/
boolean isOpen();
/**
* Return the number of milliseconds before this conversation may be closed by the container if it is inactive, i.e.
* no messages are either sent or received in that time.
*
* @return the timeout in milliseconds.
*/
long getMaxIdleTimeout();
/**
* Set the non-zero number of milliseconds before this session will be closed by the container if it is inactive, ie
* no messages are either sent or received. A value that is 0 or negative indicates the session will never timeout
* due to inactivity.
*
* @param milliseconds the number of milliseconds.
*/
void setMaxIdleTimeout(long milliseconds);
/**
* Sets the maximum length of incoming binary messages that this Session can buffer.
*
* @param length the maximum length.
*/
void setMaxBinaryMessageBufferSize(int length);
/**
* The maximum length of incoming binary messages that this Session can buffer. If the implementation receives a
* binary message that it cannot buffer because it is too large, it must close the session with a close code of
* {@link CloseReason.CloseCodes#TOO_BIG}.
*
* @return the maximum binary message size that can be buffered.
*/
int getMaxBinaryMessageBufferSize();
/**
* Sets the maximum length of incoming text messages that this Session can buffer.
*
* @param length the maximum length.
*/
void setMaxTextMessageBufferSize(int length);
/**
* The maximum length of incoming text messages that this Session can buffer. If the implementation receives a text
* message that it cannot buffer because it is too large, it must close the session with a close code of
* {@link CloseReason.CloseCodes#TOO_BIG}.
*
* @return the maximum text message size that can be buffered.
*/
int getMaxTextMessageBufferSize();
/**
* Return a reference a RemoteEndpoint object representing the peer of this conversation that is able to send
* messages asynchronously to the peer.
*
* @return the remote endpoint.
*/
RemoteEndpoint.Async getAsyncRemote();
/**
* Return a reference a RemoteEndpoint object representing the peer of this conversation that is able to send
* messages synchronously to the peer.
*
* @return the remote endpoint.
*/
RemoteEndpoint.Basic getBasicRemote();
/**
* Returns a string containing the unique identifier assigned to this session. The identifier is assigned by the web
* socket implementation and is implementation dependent.
*
* @return the unique identifier for this session instance.
*/
String getId();
/**
* Close the current conversation with a normal status code and no reason phrase.
*
* @throws IOException if there was a connection error closing the connection.
*/
@Override
void close() throws IOException;
/**
* Close the current conversation, giving a reason for the closure. The close call causes the implementation to
* attempt notify the client of the close as soon as it can. This may cause the sending of unsent messages
* immediately prior to the close notification. After the close notification has been sent the implementation
* notifies the endpoint's onClose method. Note the websocket specification defines the acceptable uses of status
* codes and reason phrases. If the application cannot determine a suitable close code to use for the closeReason,
* it is recommended to use {@link CloseReason.CloseCodes#NO_STATUS_CODE}.
*
* @param closeReason the reason for the closure.
* @throws IOException if there was a connection error closing the connection
*/
void close(CloseReason closeReason) throws IOException;
/**
* Return the URI under which this session was opened, including the query string if there is one.
*
* @return the request URI.
*/
URI getRequestURI();
/**
* Return the request parameters associated with the request this session was opened under.
*
* @return the unmodifiable map of the request parameters.
*/
Map> getRequestParameterMap();
/**
* Return the query string associated with the request this session was opened under.
*
* @return the query string
*/
String getQueryString();
/**
* Return a map of the path parameter names and values used associated with the request this session was opened
* under.
*
* @return the unmodifiable map of path parameters. The key of the map is the parameter name, the values in the map
* are the parameter values.
*/
Map getPathParameters();
/**
* While the session is open, this method returns a Map that the developer may use to store application specific
* information relating to this session instance. The developer may retrieve information from this Map at any time
* between the opening of the session and during the onClose() method. But outside that time, any information stored
* using this Map may no longer be kept by the container. Web socket applications running on distributed
* implementations of the web container should make any application specific objects stored here
* java.io.Serializable, or the object may not be recreated after a failover.
*
* @return an editable Map of application data.
*/
Map getUserProperties();
/**
* Return the authenticated user for this Session or {@code null} if no user is authenticated for this session.
*
* @return the user principal.
*/
Principal getUserPrincipal();
/**
* Return a copy of the Set of all the open web socket sessions that represent connections to the same endpoint to
* which this session represents a connection. The Set includes the session this method is called on. These sessions
* may not still be open at any point after the return of this method. For example, iterating over the set at a
* later time may yield one or more closed sessions. Developers should use session.isOpen() to check.
*
* @return the set of sessions, open at the time of return.
*/
Set getOpenSessions();
}