Session (Atomix API Reference (2.1.0-beta2))

```
public interface Session
```
Provides an interface to communicating with a client via session events.
Sessions represent a connection between a single client and all servers in a Raft cluster. Session information is replicated via the Raft consensus algorithm, and clients can safely switch connections between servers without losing their session. All consistency guarantees are provided within the context of a session. Once a session is expired or closed, linearizability, sequential consistency, and other guarantees for events and operations are effectively lost. Session implementations guarantee linearizability for session messages by coordinating between the client and a single server at any given time. This means messages published via the Session are guaranteed to arrive on the other side of the connection exactly once and in the order in which they are sent by replicated state machines. In the event of a server-to-client message being lost, the message will be resent so long as at least one Raft server is able to communicate with the client and the client's session does not expire while switching between servers.
Messages are sent to the other side of the session using the publish(PrimitiveEvent) method:
```
   
     session.publish("myEvent", "Hello world!");
   
 
```
When the message is published, it will be queued to be sent to the other side of the connection. Raft guarantees that the message will eventually be received by the client unless the session itself times out or is closed.

Nested Class Summary

Nested Classes
Modifier and Type Interface and Description

static class Session.State
Session state enums.

Nested Classes
Modifier and Type	Interface and Description
`static class`	`Session.State` Session state enums.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`void`	`addListener(SessionEventListener listener)` Adds a state change listener to the session.
`Session.State`	`getState()` Returns the session state.
`io.atomix.cluster.NodeId`	`nodeId()` Returns the node identifier to which the session belongs.
`default void`	`publish(EventType eventType)` Publishes an empty event to the session.
`default void`	`publish(EventType eventType, byte[] event)` Publishes an event to the session.
`default <T> void`	`publish(EventType eventType, Function<T,byte[]> encoder, T event)` Publishes an event to the session.
`void`	`publish(PrimitiveEvent event)` Publishes an event to the session.
`void`	`removeListener(SessionEventListener listener)` Removes a state change listener from the session.
`String`	`serviceName()` Returns the session's service name.
`PrimitiveType`	`serviceType()` Returns the session's service type.
`SessionId`	`sessionId()` Returns the session identifier.

- Method Detail
  - sessionId
```
SessionId sessionId()
```
    Returns the session identifier.
    
    Returns:
    
    The session identifier.
  - serviceName
```
String serviceName()
```
    Returns the session's service name.
    
    Returns:
    
    The session's service name.
  - serviceType
```
PrimitiveType serviceType()
```
    Returns the session's service type.
    
    Returns:
    
    The session's service type.
  - nodeId
```
io.atomix.cluster.NodeId nodeId()
```
    Returns the node identifier to which the session belongs.
    
    Returns:
    
    The node to which the session belongs.
  - getState
```
Session.State getState()
```
    Returns the session state.
    
    Returns:
    
    The session state.
  - addListener
```
void addListener(SessionEventListener listener)
```
    Adds a state change listener to the session.
    
    Parameters:
    
    listener - the state change listener to add
  - removeListener
```
void removeListener(SessionEventListener listener)
```
    Removes a state change listener from the session.
    
    Parameters:
    
    listener - the state change listener to remove
  - publish
```
default void publish(EventType eventType)
```
    Publishes an empty event to the session.
    
    Parameters:
    
    eventType - the event type
  - publish
```
default <T> void publish(EventType eventType,
                         Function<T,byte[]> encoder,
                         T event)
```
    Publishes an event to the session.
    
    Type Parameters:
    
    T - the event type
    
    Parameters:
    
    eventType - the event identifier
    
    encoder - the event value encoder
    
    event - the event value
  - publish
```
default void publish(EventType eventType,
                     byte[] event)
```
    Publishes an event to the session.
    
    Parameters:
    
    eventType - the event identifier
    
    event - the event to publish
    
    Throws:
    
    NullPointerException - if the event is null
  - publish
```
void publish(PrimitiveEvent event)
```
    Publishes an event to the session.
    
    Parameters:
    
    event - the event to publish

Interface Session

Nested Class Summary

Method Summary

Method Detail

sessionId

serviceName

serviceType

nodeId

getState

addListener

removeListener

publish

publish

publish

publish