org.jgroups.protocols

## Class STOMP

- java.lang.Object
- - org.jgroups.stack.Protocol
  - - org.jgroups.protocols.STOMP

All Implemented Interfaces:
  java.lang.Runnable

    public class STOMP
    extends Protocol
    implements java.lang.Runnable

Protocol which provides STOMP (http://stomp.codehaus.org/) support. Very simple implementation, with a one-thread-per-connection model. Use for a few hundred clients max.

The intended use for this protocol is pub-sub with clients which handle text messages, e.g. stock updates, SMS messages to mobile clients, SNMP traps etc.

Note that the full STOMP protocol has not yet been implemented, e.g. transactions are not supported. todo: use a thread pool to handle incoming frames and to send messages to clients

todo: add PING to test health of client connections

Since:
  2.11
Author:
  Bela Ban

### Nested Class Summary

Nested Classes
`static class` `STOMP.ClientVerb`
`class` `STOMP.Connection` Class which handles a connection to a client
`static class` `STOMP.Frame`
`static class` `STOMP.ServerVerb`
`static class` `STOMP.StompHeader`

### Field Summary

Fields
`protected java.lang.Thread` `acceptor`
`protected java.net.InetAddress` `bind_addr`
`protected java.util.List<STOMP.Connection>` `connections`
`protected java.lang.String` `endpoint`
`protected java.lang.String` `endpoint_addr`
`protected java.util.Map<Address,java.lang.String>` `endpoints`
`protected boolean` `exact_destination_match`
`protected boolean` `forward_non_client_generated_msgs`
`protected Address` `local_addr`
`static byte` `NULL_BYTE`
`protected int` `port`
`protected boolean` `send_info`
`protected java.net.ServerSocket` `srv_sock`
`protected java.util.concurrent.ConcurrentMap<java.lang.String,java.util.Set<STOMP.Connection>>` `subscriptions`
`protected View` `view`

### Fields inherited from class org.jgroups.stack.Protocol

`down_prot, ergonomics, id, log, name, stack, stats, up_prot`

### Constructor Summary

Constructors
Constructor and Description
`STOMP()`

### Method Summary

Methods
`protected void` `broadcastEndpoint()`
`java.lang.Object` `down(Event evt)` An event is to be sent down the stack.
`protected java.lang.String` `getAllEndpoints()`
`java.lang.String` `getEndpoints()`
`int` `getNumConnections()`
`int` `getNumSubscriptions()`
`java.lang.String` `getSubscriptions()`
`protected void` `handleView(View view)`
`static STOMP.Frame` `readFrame(java.io.DataInputStream in)`
`void` `run()`
`void` `start()` This method is called on a `Channel.connect(String)`.
`void` `stop()` This method is called on a `Channel.disconnect()`.
`java.lang.Object` `up(Event evt)` An event was received from the layer below.

### Methods inherited from class org.jgroups.stack.Protocol

`destroy, downThreadEnabled, dumpStats, enableStats, getConfigurableObjects, getDownProtocol, getId, getLevel, getName, getProperties, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getValue, init, isErgonomics, printStats, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, resetStats, setDownProtocol, setErgonomics, setId, setLevel, setProperties, setPropertiesInternal, setProperty, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, statsEnabled, upThreadEnabled`

### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

### Field Detail

#### bind_addr

    protected java.net.InetAddress bind_addr

#### endpoint_addr

    protected java.lang.String endpoint_addr

#### port

    protected int port

#### exact_destination_match

    protected boolean exact_destination_match

#### send_info

    protected boolean send_info

#### forward_non_client_generated_msgs

    protected boolean forward_non_client_generated_msgs

#### local_addr

    protected Address local_addr

#### srv_sock

    protected java.net.ServerSocket srv_sock

#### endpoint

    protected java.lang.String endpoint

#### acceptor

    protected java.lang.Thread acceptor

#### connections

    protected final java.util.List<STOMP.Connection> connections

#### endpoints

    protected final java.util.Map<Address,java.lang.String> endpoints

#### view

    protected View view

#### subscriptions

    protected final java.util.concurrent.ConcurrentMap<java.lang.String,java.util.Set<STOMP.Connection>> subscriptions

#### NULL_BYTE

    public static final byte NULL_BYTE

See Also:
  Constant Field Values

### Constructor Detail

#### STOMP

    public STOMP()

### Method Detail

#### getNumConnections

    public int getNumConnections()

#### getNumSubscriptions

    public int getNumSubscriptions()

#### getSubscriptions

    public java.lang.String getSubscriptions()

#### getEndpoints

    public java.lang.String getEndpoints()

#### start

    public void start()
               throws java.lang.Exception

Description copied from class: `Protocol`
This method is called on a `Channel.connect(String)`. Starts work. Protocols are connected and queues are ready to receive events. Will be called from bottom to top. This call will replace the START and START_OK events.

Overrides:
  `start` in class `Protocol`
Throws:
  `java.lang.Exception` - Thrown if protocol cannot be started successfully. This will cause the ProtocolStack to fail, so `Channel.connect(String)` will throw an exception

#### stop

    public void stop()

Description copied from class: `Protocol`
This method is called on a `Channel.disconnect()`. Stops work (e.g. by closing multicast socket). Will be called from top to bottom. This means that at the time of the method invocation the neighbor protocol below is still working. This method will replace the STOP, STOP_OK, CLEANUP and CLEANUP_OK events. The ProtocolStack guarantees that when this method is called all messages in the down queue will have been flushed

Overrides:
  `stop` in class `Protocol`

#### run

    public void run()

Specified by:
  `run` in interface `java.lang.Runnable`

#### down

    public java.lang.Object down(Event evt)

Description copied from class: `Protocol`
An event is to be sent down the stack. The layer may want to examine its type and perform some action on it, depending on the event's type. If the event is a message MSG, then the layer may need to add a header to it (or do nothing at all) before sending it down the stack using `down_prot.down()`. In case of a GET_ADDRESS event (which tries to retrieve the stack's address from one of the bottom layers), the layer may need to send a new response event back up the stack using `up_prot.up()`.

Overrides:
  `down` in class `Protocol`

#### up

    public java.lang.Object up(Event evt)

Description copied from class: `Protocol`
An event was received from the layer below. Usually the current layer will want to examine the event type and - depending on its type - perform some computation (e.g. removing headers from a MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event). Finally the event is either a) discarded, or b) an event is sent down the stack using `down_prot.down()` or c) the event (or another event) is sent up the stack using `up_prot.up()`.

Overrides:
  `up` in class `Protocol`

#### readFrame

    public static STOMP.Frame readFrame(java.io.DataInputStream in)
                                 throws java.io.IOException

Throws:
  `java.io.IOException`

#### handleView

    protected void handleView(View view)

#### getAllEndpoints

    protected java.lang.String getAllEndpoints()

#### broadcastEndpoint

    protected void broadcastEndpoint()