MuxChannel

java.lang.Object
- org.jgroups.Channel
- - org.jgroups.JChannel
  - - org.jgroups.mux.MuxChannel

All Implemented Interfaces:

Transport
```
public class MuxChannel
extends JChannel
```
Multiplexer channel. This is returned as result of calling ChannelFactory.createMultiplexerChannel(String,String,boolean,String). Maintains the multiplexer ID, which is used to add a header to each message, so that the message can be demultiplexed at the receiver

Version:

$Id: MuxChannel.java,v 1.26.2.1 2007/01/08 21:00:16 vlada Exp $

Author:

Bela Ban

Field Summary
- Fields inherited from class org.jgroups.JChannel
  closed, closer, connected, DEFAULT_PROTOCOL_STACK, log, received_bytes, received_msgs, sent_bytes, sent_msgs, stats
- Fields inherited from class org.jgroups.Channel
  AUTO_GETSTATE, AUTO_RECONNECT, BLOCK, channel_listener, channel_listeners, GET_STATE_EVENTS, LOCAL, receiver, SUSPECT, up_handler, VIEW

Constructor Summary

Constructors
Constructor and Description
`MuxChannel(JChannelFactory f, JChannel ch, java.lang.String id, java.lang.String stack_name, Multiplexer mux)`

Method Summary

Methods
Modifier and Type	Method and Description
`protected void`	`_close(boolean disconnect, boolean close_mq)` Disconnects and closes the channel.
`protected void`	`checkClosed()` health check throws a ChannelClosed exception if the channel is closed
`protected void`	`checkNotConnected()` health check. throws a ChannelNotConnected exception if the channel is not connected
`void`	`close()` Destroys the channel.
`void`	`connect(java.lang.String channel_name)` Connects the channel to a group.
`boolean`	`connect(java.lang.String cluster_name, Address target, java.lang.String state_id, long timeout)` Connects the channel to a group and fetches the state
`void`	`disconnect()` Disconnects the channel if it is connected.
`void`	`down(Event evt)` Sends a message through the protocol stack if the stack is available
`java.util.Map`	`dumpStats()` Returns a map of statistics of the various protocols and of the channel itself.
`JChannel`	`getChannel()` This should never be used (just for testing) !
`java.lang.String`	`getChannelName()` returns the name of the channel if the channel is not connected or if it is closed it will return null
`java.lang.String`	`getClusterName()` Returns the cluster name of the group of which the channel is a member.
`View`	`getClusterView()` Returns the JGroups view of a cluster, e.g.
`java.lang.String`	`getId()`
`Address`	`getLocalAddress()` returns the local address of the channel returns null if the channel is closed
`Multiplexer`	`getMultiplexer()`
`java.lang.Object`	`getOpt(int option)` returns the value of an option.
`ProtocolStack`	`getProtocolStack()` Returns the protocol stack.
`java.lang.String`	`getStackName()`
`boolean`	`getState(Address target, long timeout)` Retrieves the current group state.
`boolean`	`getState(Address target, java.lang.String state_id, long timeout)` Retrieves a substate (or partial state) from the target.
`View`	`getView()` Returns the service view, ie.
`boolean`	`isConnected()` returns true if the Connect operation has been called successfully
`boolean`	`isOpen()` returns true if the Open operation has been called successfully
`void`	`open()` Opens the channel.
`void`	`returnState(byte[] state)` Called by the application is response to receiving a `getState()` object when calling `receive()`.
`void`	`returnState(byte[] state, java.lang.String state_id)` Returns a substate as indicated by state_id
`void`	`send(Address dst, Address src, java.io.Serializable obj)` creates a new message with the destination address, and the source address and the object as the message value
`void`	`send(Message msg)` Sends a message through the protocol stack.
`void`	`setClosed(boolean f)`
`void`	`setConnected(boolean f)`
`void`	`setOpt(int option, java.lang.Object value)` Sets a channel option.
`void`	`shutdown()` Shuts down the channel without disconnecting

Methods inherited from class org.jgroups.JChannel
blockOk, closeMessageQueue, dumpQueue, dumpTimerQueue, enableStats, flushSupported, getAllStates, getLog, getNumberOfTasksInTimer, getNumMessages, getProperties, getReceivedBytes, getReceivedMessages, getSentBytes, getSentMessages, init, peek, printProtocolSpec, receive, resetStats, startFlush, startFlush, statsEnabled, stopFlush, toString, up

Methods inherited from class org.jgroups.Channel
addChannelListener, notifyChannelClosed, notifyChannelConnected, notifyChannelDisconnected, notifyChannelReconnected, notifyChannelShunned, option2String, removeChannelListener, setChannelListener, setReceiver, setUpHandler

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - MuxChannel
```
public MuxChannel(JChannelFactory f,
          JChannel ch,
          java.lang.String id,
          java.lang.String stack_name,
          Multiplexer mux)
```
- Method Detail
  - getStackName
```
public java.lang.String getStackName()
```
  - getId
```
public java.lang.String getId()
```
  - getMultiplexer
```
public Multiplexer getMultiplexer()
```
  - getChannelName
```
public java.lang.String getChannelName()
```
    Description copied from class: JChannel
    
    returns the name of the channel if the channel is not connected or if it is closed it will return null
    
    Overrides:
    
    getChannelName in class JChannel
    
    Returns:
    The group address
  - getClusterName
```
public java.lang.String getClusterName()
```
    Description copied from class: Channel
    
    Returns the cluster name of the group of which the channel is a member. This is the object that was the argument to connect(). Calling this method on a closed channel returns null.
    
    Overrides:
    
    getClusterName in class JChannel
    
    Returns:
    The cluster name
  - getLocalAddress
```
public Address getLocalAddress()
```
    Description copied from class: JChannel
    
    returns the local address of the channel returns null if the channel is closed
    
    Overrides:
    
    getLocalAddress in class JChannel
    
    Returns:
    The channel's address. Generated by the underlying transport, and opaque. Addresses can be used as destination in the Send operation.
  - getChannel
```
public JChannel getChannel()
```
    This should never be used (just for testing) !
  - getView
```
public View getView()
```
    Returns the service view, ie. the cluster view (see getView()) minus the nodes on which this service is not running, e.g. if S1 runs on A and C, and the cluster view is {A,B,C}, then the service view is {A,C}
    
    Overrides:
    
    getView in class JChannel
    
    Returns:
    The service view (list of nodes on which this service is running)
  - getClusterView
```
public View getClusterView()
```
    Returns the JGroups view of a cluster, e.g. if we have nodes A, B and C, then the view will be {A,B,C}
    
    Returns:
    The JGroups view
  - getProtocolStack
```
public ProtocolStack getProtocolStack()
```
    Description copied from class: JChannel
    
    Returns the protocol stack. Currently used by Debugger. Specific to JChannel, therefore not visible in Channel
    
    Overrides:
    
    getProtocolStack in class JChannel
  - isOpen
```
public boolean isOpen()
```
    Description copied from class: JChannel
    
    returns true if the Open operation has been called successfully
    
    Overrides:
    
    isOpen in class JChannel
  - isConnected
```
public boolean isConnected()
```
    Description copied from class: JChannel
    
    returns true if the Connect operation has been called successfully
    
    Overrides:
    
    isConnected in class JChannel
  - dumpStats
```
public java.util.Map dumpStats()
```
    Description copied from class: JChannel
    
    Returns a map of statistics of the various protocols and of the channel itself.
    
    Overrides:
    
    dumpStats in class JChannel
    
    Returns:
    Map. A map where the keys are the protocols ("channel" pseudo key is used for the channel itself") and the values are property maps.
  - setClosed
```
public void setClosed(boolean f)
```
  - setConnected
```
public void setConnected(boolean f)
```
  - getOpt
```
public java.lang.Object getOpt(int option)
```
    Description copied from class: JChannel
    
    returns the value of an option.
    
    Overrides:
    
    getOpt in class JChannel
    
    Parameters:
    option - the option you want to see the value for
    
    Returns:
    the object value, in most cases java.lang.Boolean
    See Also:
    JChannel.setOpt(int, java.lang.Object)
  - setOpt
```
public void setOpt(int option,
          java.lang.Object value)
```
    Description copied from class: JChannel
    Sets a channel option. The options can be one of the following:
    - Channel.BLOCK
    - Channel.LOCAL
    - Channel.AUTO_RECONNECT
    - Channel.AUTO_GETSTATE
    There are certain dependencies between the options that you can set, I will try to describe them here.
    Option: Channel.BLOCK
    Value: java.lang.Boolean
    Result: set to true will set setOpt(VIEW, true) and the JChannel will receive BLOCKS and VIEW events
    
    Option: LOCAL
    Value: java.lang.Boolean
    Result: set to true the JChannel will receive messages that it self sent out.
    
    Option: AUTO_RECONNECT
    Value: java.lang.Boolean
    Result: set to true and the JChannel will try to reconnect when it is being closed
    
    Option: AUTO_GETSTATE
    Value: java.lang.Boolean
    Result: set to true, the AUTO_RECONNECT will be set to true and the JChannel will try to get the state after a close and reconnect happens
    Overrides:
    
    setOpt in class JChannel
    
    Parameters:
    option - the parameter option Channel.VIEW, Channel.SUSPECT, etc
    value - the value to set for this option
  - connect
```
public void connect(java.lang.String channel_name)
             throws ChannelException,
                    ChannelClosedException
```
    Description copied from class: JChannel
    
    Connects the channel to a group. If the channel is already connected, an error message will be printed to the error log. If the channel is closed a ChannelClosed exception will be thrown. This method starts the protocol stack by calling ProtocolStack.start, then it sends an Event.CONNECT event down the stack and waits to receive a CONNECT_OK event. Once the CONNECT_OK event arrives from the protocol stack, any channel listeners are notified and the channel is considered connected.
    
    Overrides:
    
    connect in class JChannel
    
    Parameters:
    channel_name - A String denoting the group name. Cannot be null.
    
    Throws:
    
    ChannelException - The protocol stack cannot be started
    
    ChannelClosedException - The channel is closed and therefore cannot be used any longer. A new channel has to be created first.
    See Also:
    Channel.disconnect()
  - connect
```
public boolean connect(java.lang.String cluster_name,
              Address target,
              java.lang.String state_id,
              long timeout)
                throws ChannelException
```
    Description copied from class: Channel
    
    Connects the channel to a group and fetches the state
    
    Overrides:
    
    connect in class JChannel
    
    state_id - The ID of a substate. If the full state is to be fetched, set this to null
    
    Returns:
    True if the state could be fetched, otherwise false. If true is returned, the state setting method (e.g. setState() will be called.
    
    Throws:
    
    ChannelException
  - disconnect
```
public void disconnect()
```
    Description copied from class: JChannel
    Disconnects the channel if it is connected. If the channel is closed, this operation is ignored
    Otherwise the following actions happen in the listed order
    1. The JChannel sends a DISCONNECT event down the protocol stack
    2. Blocks until the channel to receives a DISCONNECT_OK event
    3. Sends a STOP_QUEING event down the stack
    4. Stops the protocol stack by calling ProtocolStack.stop()
    5. Notifies the listener, if the listener is available
    Overrides:
    
    disconnect in class JChannel
    
    See Also:
    Channel.connect(String)
  - open
```
public void open()
          throws ChannelException
```
    Description copied from class: JChannel
    Opens the channel. This does the following actions:
    1. Resets the receiver queue by calling Queue.reset
    2. Sets up the protocol stack by calling ProtocolStack.setup
    3. Sets the closed flag to false
    Overrides:
    
    open in class JChannel
    
    Throws:
    
    ChannelException
  - close
```
public void close()
```
    Description copied from class: JChannel
    
    Destroys the channel. After this method has been called, the channel us unusable.
    This operation will disconnect the channel and close the channel receive queue immediately
    
    Overrides:
    
    close in class JChannel
  - _close
```
protected void _close(boolean disconnect,
          boolean close_mq)
```
    Description copied from class: JChannel
    Disconnects and closes the channel. This method does the folloing things
    1. Calls this.disconnect if the disconnect parameter is true
    2. Calls Queue.close on mq if the close_mq parameter is true
    3. Calls ProtocolStack.stop on the protocol stack
    4. Calls ProtocolStack.destroy on the protocol stack
    5. Sets the channel closed and channel connected flags to true and false
    6. Notifies any channel listener of the channel close operation
    Overrides:
    
    _close in class JChannel
  - shutdown
```
public void shutdown()
```
    Description copied from class: JChannel
    
    Shuts down the channel without disconnecting
    
    Overrides:
    
    shutdown in class JChannel
  - send
```
public void send(Message msg)
          throws ChannelNotConnectedException,
                 ChannelClosedException
```
    Description copied from class: JChannel
    
    Sends a message through the protocol stack. Implements the Transport interface.
    
    Specified by:
    
    send in interface Transport
    
    Overrides:
    
    send in class JChannel
    
    Parameters:
    msg - the message to be sent through the protocol stack, the destination of the message is specified inside the message itself
    
    Throws:
    
    ChannelNotConnectedException - The channel must be connected to send messages.
    
    ChannelClosedException - The channel is closed and therefore cannot be used any longer. A new channel has to be created first.
  - send
```
public void send(Address dst,
        Address src,
        java.io.Serializable obj)
          throws ChannelNotConnectedException,
                 ChannelClosedException
```
    Description copied from class: JChannel
    
    creates a new message with the destination address, and the source address and the object as the message value
    
    Overrides:
    
    send in class JChannel
    
    Parameters:
    dst - - the destination address of the message, null for all members
    src - - the source address of the message
    obj - - the value of the message
    
    Throws:
    
    ChannelNotConnectedException
    
    ChannelClosedException
    See Also:
    JChannel.send(org.jgroups.Message)
  - down
```
public void down(Event evt)
```
    Description copied from class: JChannel
    
    Sends a message through the protocol stack if the stack is available
    
    Overrides:
    
    down in class JChannel
    
    Parameters:
    evt - the message to send down, encapsulated in an event
  - getState
```
public boolean getState(Address target,
               long timeout)
                 throws ChannelNotConnectedException,
                        ChannelClosedException
```
    Description copied from class: JChannel
    
    Retrieves the current group state. Sends GET_STATE event down to STATE_TRANSFER layer. Blocks until STATE_TRANSFER sends up a GET_STATE_OK event or until timeout milliseconds have elapsed. The argument of GET_STATE_OK should be a single object.
    
    Overrides:
    
    getState in class JChannel
    
    Parameters:
    target - the target member to receive the state from. if null, state is retrieved from coordinator
    timeout - the number of milliseconds to wait for the operation to complete successfully. 0 waits until the state has been received
    
    Returns:
    true of the state was received, false if the operation timed out
    
    Throws:
    
    ChannelNotConnectedException - The channel must be connected to receive messages.
    
    ChannelClosedException - The channel is closed and therefore cannot be used any longer. A new channel has to be created first.
  - getState
```
public boolean getState(Address target,
               java.lang.String state_id,
               long timeout)
                 throws ChannelNotConnectedException,
                        ChannelClosedException
```
    Description copied from class: JChannel
    
    Retrieves a substate (or partial state) from the target.
    
    Overrides:
    
    getState in class JChannel
    
    Parameters:
    target - State provider. If null, coordinator is used
    state_id - The ID of the substate. If null, the entire state will be transferred
    timeout - the number of milliseconds to wait for the operation to complete successfully. 0 waits until the state has been received
    
    Returns:
    
    Throws:
    
    ChannelNotConnectedException
    
    ChannelClosedException
  - returnState
```
public void returnState(byte[] state)
```
    Description copied from class: JChannel
    
    Called by the application is response to receiving a getState() object when calling receive(). When the application receives a getState() message on the receive() method, it should call returnState() to reply with the state of the application
    
    Overrides:
    
    returnState in class JChannel
    
    Parameters:
    state - The state of the application as a byte buffer (to send over the network).
  - returnState
```
public void returnState(byte[] state,
               java.lang.String state_id)
```
    Description copied from class: JChannel
    
    Returns a substate as indicated by state_id
    
    Overrides:
    
    returnState in class JChannel
  - checkNotConnected
```
protected void checkNotConnected()
                          throws ChannelNotConnectedException
```
    Description copied from class: JChannel
    
    health check.
    throws a ChannelNotConnected exception if the channel is not connected
    
    Overrides:
    
    checkNotConnected in class JChannel
    
    Throws:
    
    ChannelNotConnectedException
  - checkClosed
```
protected void checkClosed()
                    throws ChannelClosedException
```
    Description copied from class: JChannel
    
    health check
    throws a ChannelClosed exception if the channel is closed
    
    Overrides:
    
    checkClosed in class JChannel
    
    Throws:
    
    ChannelClosedException

Class MuxChannel

Field Summary

Fields inherited from class org.jgroups.JChannel

Fields inherited from class org.jgroups.Channel

Constructor Summary

Method Summary

Methods inherited from class org.jgroups.JChannel

Methods inherited from class org.jgroups.Channel

Methods inherited from class java.lang.Object

Constructor Detail

MuxChannel

Method Detail

getStackName

getId

getMultiplexer

getChannelName

getClusterName

getLocalAddress

getChannel

getView

getClusterView

getProtocolStack

isOpen

isConnected

dumpStats

setClosed

setConnected

getOpt

setOpt

connect

connect

disconnect

open

close

_close

shutdown

send

send

down

getState

getState

returnState

returnState

checkNotConnected

checkClosed