MessageQueue (QpidJMS Client 0.8.0 API)

All Known Implementing Classes:

AbstractMessageQueue, FifoMessageQueue, PriorityMessageQueue
```
public interface MessageQueue
```
Queue based storage interface for inbound Messages.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clear()` Clears the Queue of any Messages.
`void`	`close()` Closes the Message Queue.
`JmsInboundMessageDispatch`	`dequeue(long timeout)` Used to get an enqueued message.
`JmsInboundMessageDispatch`	`dequeueNoWait()` Used to get an enqueued Message if on exists, otherwise returns null.
`void`	`enqueue(JmsInboundMessageDispatch envelope)` Adds the given message envelope to the end of the Message queue.
`void`	`enqueueFirst(JmsInboundMessageDispatch envelope)` Adds the given message envelope to the front of the Message queue.
`Object`	`getLock()`
`boolean`	`isClosed()`
`boolean`	`isEmpty()`
`boolean`	`isRunning()`
`JmsInboundMessageDispatch`	`peek()` Return but do not remove the first element in the Message queue.
`List<JmsInboundMessageDispatch>`	`removeAll()` Removes and returns all Messages in the Queue.
`int`	`size()` Returns the number of Messages currently in the Queue.
`void`	`start()` Starts the Message Queue.
`void`	`stop()` Stops the Message Queue.

- Method Detail
  - enqueue
```
void enqueue(JmsInboundMessageDispatch envelope)
```
    Adds the given message envelope to the end of the Message queue.
    
    Parameters:
    envelope - The in-bound Message envelope to enqueue.
  - enqueueFirst
```
void enqueueFirst(JmsInboundMessageDispatch envelope)
```
    Adds the given message envelope to the front of the Message queue.
    
    Parameters:
    envelope - The in-bound Message envelope to enqueue.
  - isEmpty
```
boolean isEmpty()
```
    Returns:
    true if there are no messages in the queue.
  - peek
```
JmsInboundMessageDispatch peek()
```
    Return but do not remove the first element in the Message queue.
    
    Returns:
    the first element in the Queue or null if empty.
  - dequeue
```
JmsInboundMessageDispatch dequeue(long timeout)
                                  throws InterruptedException
```
    Used to get an enqueued message. The amount of time this method blocks is based on the timeout value. - if timeout==-1 then it blocks until a message is received. - if timeout==0 then it it tries to not block at all, it returns a message if it is available - if timeout > 0 then it blocks up to timeout amount of time. Expired messages will consumed by this method.
    
    Parameters:
    timeout - The amount of time to wait for an entry to be added before returning null.
    
    Returns:
    null if we timeout or if the consumer is closed.
    
    Throws:
    
    InterruptedException - if the wait is interrupted.
  - dequeueNoWait
```
JmsInboundMessageDispatch dequeueNoWait()
```
    Used to get an enqueued Message if on exists, otherwise returns null.
    
    Returns:
    the next Message in the Queue if one exists, otherwise null.
  - start
```
void start()
```
    Starts the Message Queue. An non-started Queue will always return null for any of the Queue methods.
  - stop
```
void stop()
```
    Stops the Message Queue. Messages cannot be read from the Queue when it is in the stopped state and any waiters will be awoken.
  - isRunning
```
boolean isRunning()
```
    Returns:
    true if the Queue is not in the stopped or closed state.
  - close
```
void close()
```
    Closes the Message Queue. No messages can be added or removed from the Queue once it has entered the closed state.
  - isClosed
```
boolean isClosed()
```
    Returns:
    true if the Queue has been closed.
  - size
```
int size()
```
    Returns the number of Messages currently in the Queue. This value is only meaningful at the time of the call as the size of the Queue changes rapidly as Messages arrive and are consumed.
    
    Returns:
    the current number of Messages in the Queue.
  - clear
```
void clear()
```
    Clears the Queue of any Messages.
  - removeAll
```
List<JmsInboundMessageDispatch> removeAll()
```
    Removes and returns all Messages in the Queue.
    
    Returns:
    a List containing all Messages removed from the Queue.
  - getLock
```
Object getLock()
```
    Returns:
    the lock object used to protect against concurrent access.

Interface MessageQueue

Method Summary

Method Detail

enqueue

enqueueFirst

isEmpty

peek

dequeue

dequeueNoWait

start

stop

isRunning

close

isClosed

size

clear

removeAll

getLock