/*
* 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 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.
* <p/>
* Once the session is closed, it is no longer valid for use by applications.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 IllegalStateException being
* thrown. Developers should retrieve any information from the session during the
* Endpoint.onClose(javax.websocket.Session, javax.websocket.CloseReason) method. Following the convention of Closeable
* calling the Session close() methods after the Session has been closed has no effect.
* <p/>
* Session objects may be called by multiple threads. Implementations must ensure the integrity of the mutable
* properties of the session under such circumstances.
*/
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 MessageHandler.Whole and MessageHandler.Partial. Adding more than
* one of any one type will result in a runtime exception.
* <p/>
* See Endpoint for a usage example.
*
* @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;
/**
* Return an unmodifiable copy of the set of MessageHandlers for this Session.
*
* @return the set of message handlers.
*/
Set<MessageHandler> 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<Extension> 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
* 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
* 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 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<String, List<String>> 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<String, String> 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<String, Object> getUserProperties();
/**
* Return the authenticated user for this Session or 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<Session> getOpenSessions();
}