java.lang.Object
- org.apache.activemq.ActiveMQMessageConsumer

All Implemented Interfaces:

MessageConsumer, ActiveMQDispatcher, StatsCapable, MessageAvailableConsumer

Direct Known Subclasses:

ActiveMQQueueReceiver, ActiveMQTopicSubscriber
```
public class ActiveMQMessageConsumer
extends Object
implements MessageAvailableConsumer, StatsCapable, ActiveMQDispatcher
```
A client uses a MessageConsumer object to receive messages from a destination. A MessageConsumer object is created by passing a Destination object to a message-consumer creation method supplied by a session.
MessageConsumer is the parent interface for all message consumers.
A message consumer can be created with a message selector. A message selector allows the client to restrict the messages delivered to the message consumer to those that match the selector.
A client may either synchronously receive a message consumer's messages or have the consumer asynchronously deliver them as they arrive.
For synchronous receipt, a client can request the next message from a message consumer using one of its receive methods. There are several variations of receive that allow a client to poll or wait for the next message.
For asynchronous delivery, a client can register a MessageListener object with a message consumer. As messages arrive at the message consumer, it delivers them by calling the MessageListener'sonMessage method.
It is a client programming error for a MessageListener to throw an exception.

See Also:

MessageConsumer, QueueReceiver, TopicSubscriber, Session

Field Summary

Fields
Modifier and Type	Field	Description
`protected LinkedList<MessageDispatch>`	`deliveredMessages`
`protected ConsumerInfo`	`info`
`protected ActiveMQSession`	`session`
`protected MessageDispatchChannel`	`unconsumedMessages`

Constructor Summary

Constructors
Constructor	Description
`ActiveMQMessageConsumer(ActiveMQSession session, ConsumerId consumerId, ActiveMQDestination dest, String name, String selector, int prefetch, int maximumPendingMessageCount, boolean noLocal, boolean browser, boolean dispatchAsync, MessageListener messageListener)`	Create a MessageConsumer

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`acknowledge()`	Acknowledge all the messages that have been delivered to the client up to this point.
`protected void`	`checkClosed()`
`protected void`	`checkMessageListener()`
`void`	`close()`	Closes the message consumer.
`void`	`commit()`
`void`	`dispatch(MessageDispatch md)`
`void`	`dispose()`
`MessageAvailableListener`	`getAvailableListener()`	Gets the listener used to notify synchronous consumers that there is a message available so that the `MessageConsumer.receiveNoWait()` can be called.
`ConsumerId`	`getConsumerId()`
`String`	`getConsumerName()`
`JMSConsumerStatsImpl`	`getConsumerStats()`
`protected ActiveMQDestination`	`getDestination()`
`IOException`	`getFailureError()`
`long`	`getLastDeliveredSequenceId()`
`MessageListener`	`getMessageListener()`	Gets the message consumer's `MessageListener`.
`String`	`getMessageSelector()`	Gets this message consumer's message selector expression.
`int`	`getMessageSize()`
`long`	`getOptimizedAckScheduledAckInterval()`
`int`	`getPrefetchNumber()`
`RedeliveryPolicy`	`getRedeliveryPolicy()`
`StatsImpl`	`getStats()`
`MessageTransformer`	`getTransformer()`
`boolean`	`hasMessageListener()`
`protected boolean`	`isBrowser()`	Retrieve is a browser
`boolean`	`isConsumerExpiryCheckEnabled()`
`boolean`	`isDurableSubscriber()`
`boolean`	`isInUse(ActiveMQTempDestination destination)`
`protected boolean`	`isNoLocal()`
`boolean`	`iterate()`	Delivers a message to the message listener.
`Message`	`receive()`	Receives the next message produced for this message consumer.
`Message`	`receive(long timeout)`	Receives the next message that arrives within the specified timeout interval.
`Message`	`receiveNoWait()`	Receives the next message if one is immediately available.
`void`	`rollback()`
`protected void`	`sendPullCommand(long timeout)`	If we have a zero prefetch specified then send a pull command to the broker to pull a message we are about to receive
`void`	`setAvailableListener(MessageAvailableListener availableListener)`	Sets the listener used to notify synchronous consumers that there is a message available so that the `MessageConsumer.receiveNoWait()` can be called.
`void`	`setConsumerExpiryCheckEnabled(boolean consumerExpiryCheckEnabled)`
`void`	`setFailureError(IOException failureError)`
`void`	`setMessageListener(MessageListener listener)`	Sets the message consumer's `MessageListener`.
`protected void`	`setOptimizeAcknowledge(boolean value)`
`void`	`setOptimizedAckScheduledAckInterval(long optimizedAckScheduledAckInterval)`
`protected void`	`setPrefetchSize(int prefetch)`
`void`	`setRedeliveryPolicy(RedeliveryPolicy redeliveryPolicy)`	Sets the redelivery policy used when messages are redelivered
`void`	`setTransformer(MessageTransformer transformer)`	Sets the transformer used to transform messages before they are sent on to the JMS bus
`void`	`start()`
`void`	`stop()`
`String`	`toString()`

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

- Field Detail
  - session
```
protected final ActiveMQSession session
```
  - info
```
protected final ConsumerInfo info
```
  - unconsumedMessages
```
protected final MessageDispatchChannel unconsumedMessages
```
  - deliveredMessages
```
protected final LinkedList<MessageDispatch> deliveredMessages
```
- Constructor Detail
  - ActiveMQMessageConsumer
```
public ActiveMQMessageConsumer(ActiveMQSession session,
                               ConsumerId consumerId,
                               ActiveMQDestination dest,
                               String name,
                               String selector,
                               int prefetch,
                               int maximumPendingMessageCount,
                               boolean noLocal,
                               boolean browser,
                               boolean dispatchAsync,
                               MessageListener messageListener)
                        throws JMSException
```
    Create a MessageConsumer
    
    Parameters:
    
    session -
    
    dest -
    
    name -
    
    selector -
    
    prefetch -
    
    maximumPendingMessageCount -
    
    noLocal -
    
    browser -
    
    dispatchAsync -
    
    messageListener -
    
    Throws:
    
    JMSException
- Method Detail
  - getStats
```
public StatsImpl getStats()
```
    Specified by:
    
    getStats in interface StatsCapable
    
    Returns:
    
    the Stats for this object
  - getConsumerStats
```
public JMSConsumerStatsImpl getConsumerStats()
```
  - getRedeliveryPolicy
```
public RedeliveryPolicy getRedeliveryPolicy()
```
  - setRedeliveryPolicy
```
public void setRedeliveryPolicy(RedeliveryPolicy redeliveryPolicy)
```
    Sets the redelivery policy used when messages are redelivered
  - getTransformer
```
public MessageTransformer getTransformer()
```
  - setTransformer
```
public void setTransformer(MessageTransformer transformer)
```
    Sets the transformer used to transform messages before they are sent on to the JMS bus
  - getConsumerId
```
public ConsumerId getConsumerId()
```
    Returns:
    
    Returns the value.
  - getConsumerName
```
public String getConsumerName()
```
    Returns:
    
    the consumer name - used for durable consumers
  - isNoLocal
```
protected boolean isNoLocal()
```
    Returns:
    
    true if this consumer does not accept locally produced messages
  - isBrowser
```
protected boolean isBrowser()
```
    Retrieve is a browser
    
    Returns:
    
    true if a browser
  - getDestination
```
protected ActiveMQDestination getDestination()
```
    Returns:
    
    ActiveMQDestination
  - getPrefetchNumber
```
public int getPrefetchNumber()
```
    Returns:
    
    Returns the prefetchNumber.
  - isDurableSubscriber
```
public boolean isDurableSubscriber()
```
    Returns:
    
    true if this is a durable topic subscriber
  - getMessageSelector
```
public String getMessageSelector()
                          throws JMSException
```
    Gets this message consumer's message selector expression.
    
    Specified by:
    
    getMessageSelector in interface MessageConsumer
    
    Returns:
    
    this message consumer's message selector, or null if no message selector exists for the message consumer (that is, if the message selector was not set or was set to null or the empty string)
    
    Throws:
    
    JMSException - if the JMS provider fails to receive the next message due to some internal error.
  - getMessageListener
```
public MessageListener getMessageListener()
                                   throws JMSException
```
    Gets the message consumer's MessageListener.
    
    Specified by:
    
    getMessageListener in interface MessageConsumer
    
    Returns:
    
    the listener for the message consumer, or null if no listener is set
    
    Throws:
    
    JMSException - if the JMS provider fails to get the message listener due to some internal error.
    
    See Also:
    
    MessageConsumer.setMessageListener(javax.jms.MessageListener)
  - setMessageListener
```
public void setMessageListener(MessageListener listener)
                        throws JMSException
```
    Sets the message consumer's MessageListener.
    Setting the message listener to null is the equivalent of unsetting the message listener for the message consumer.
    The effect of calling MessageConsumer.setMessageListener while messages are being consumed by an existing listener or the consumer is being used to consume messages synchronously is undefined.
    
    Specified by:
    
    setMessageListener in interface MessageConsumer
    
    Parameters:
    
    listener - the listener to which the messages are to be delivered
    
    Throws:
    
    JMSException - if the JMS provider fails to receive the next message due to some internal error.
    
    See Also:
    
    MessageConsumer.getMessageListener()
  - getAvailableListener
```
public MessageAvailableListener getAvailableListener()
```
    Description copied from interface: MessageAvailableConsumer
    
    Gets the listener used to notify synchronous consumers that there is a message available so that the MessageConsumer.receiveNoWait() can be called.
    
    Specified by:
    
    getAvailableListener in interface MessageAvailableConsumer
  - setAvailableListener
```
public void setAvailableListener(MessageAvailableListener availableListener)
```
    Sets the listener used to notify synchronous consumers that there is a message available so that the MessageConsumer.receiveNoWait() can be called.
    
    Specified by:
    
    setAvailableListener in interface MessageAvailableConsumer
  - receive
```
public Message receive()
                throws JMSException
```
    Receives the next message produced for this message consumer.
    This call blocks indefinitely until a message is produced or until this message consumer is closed.
    If this receive is done within a transaction, the consumer retains the message until the transaction commits.
    
    Specified by:
    
    receive in interface MessageConsumer
    
    Returns:
    
    the next message produced for this message consumer, or null if this message consumer is concurrently closed
    
    Throws:
    
    JMSException
  - receive
```
public Message receive(long timeout)
                throws JMSException
```
    Receives the next message that arrives within the specified timeout interval.
    This call blocks until a message arrives, the timeout expires, or this message consumer is closed. A timeout of zero never expires, and the call blocks indefinitely.
    
    Specified by:
    
    receive in interface MessageConsumer
    
    Parameters:
    
    timeout - the timeout value (in milliseconds), a time out of zero never expires.
    
    Returns:
    
    the next message produced for this message consumer, or null if the timeout expires or this message consumer is concurrently closed
    
    Throws:
    
    JMSException
  - receiveNoWait
```
public Message receiveNoWait()
                      throws JMSException
```
    Receives the next message if one is immediately available.
    
    Specified by:
    
    receiveNoWait in interface MessageConsumer
    
    Returns:
    
    the next message produced for this message consumer, or null if one is not available
    
    Throws:
    
    JMSException - if the JMS provider fails to receive the next message due to some internal error.
  - close
```
public void close()
           throws JMSException
```
    Closes the message consumer.
    Since a provider may allocate some resources on behalf of a MessageConsumer outside the Java virtual machine, clients should close them when they are not needed. Relying on garbage collection to eventually reclaim these resources may not be timely enough.
    This call blocks until a receive or message listener in progress has completed. A blocked message consumer receive call returns null when this message consumer is closed.
    
    Specified by:
    
    close in interface MessageConsumer
    
    Throws:
    
    JMSException - if the JMS provider fails to close the consumer due to some internal error.
  - dispose
```
public void dispose()
             throws JMSException
```
    Throws:
    
    JMSException
  - checkClosed
```
protected void checkClosed()
                    throws IllegalStateException
```
    Throws:
    
    IllegalStateException
  - sendPullCommand
```
protected void sendPullCommand(long timeout)
                        throws JMSException
```
    If we have a zero prefetch specified then send a pull command to the broker to pull a message we are about to receive
    
    Throws:
    
    JMSException
  - checkMessageListener
```
protected void checkMessageListener()
                             throws JMSException
```
    Throws:
    
    JMSException
  - setOptimizeAcknowledge
```
protected void setOptimizeAcknowledge(boolean value)
```
  - setPrefetchSize
```
protected void setPrefetchSize(int prefetch)
```
  - acknowledge
```
public void acknowledge()
                 throws JMSException
```
    Acknowledge all the messages that have been delivered to the client up to this point.
    
    Throws:
    
    JMSException
  - commit
```
public void commit()
            throws JMSException
```
    Throws:
    
    JMSException
  - rollback
```
public void rollback()
              throws JMSException
```
    Throws:
    
    JMSException
  - dispatch
```
public void dispatch(MessageDispatch md)
```
    Specified by:
    
    dispatch in interface ActiveMQDispatcher
  - getMessageSize
```
public int getMessageSize()
```
  - start
```
public void start()
           throws JMSException
```
    Throws:
    
    JMSException
  - stop
```
public void stop()
```
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - iterate
```
public boolean iterate()
```
    Delivers a message to the message listener.
    
    Returns:
    
    true if another execution is needed.
    
    Throws:
    
    JMSException
  - isInUse
```
public boolean isInUse(ActiveMQTempDestination destination)
```
  - getLastDeliveredSequenceId
```
public long getLastDeliveredSequenceId()
```
  - getFailureError
```
public IOException getFailureError()
```
  - setFailureError
```
public void setFailureError(IOException failureError)
```
  - getOptimizedAckScheduledAckInterval
```
public long getOptimizedAckScheduledAckInterval()
```
    Returns:
    
    the optimizedAckScheduledAckInterval
  - setOptimizedAckScheduledAckInterval
```
public void setOptimizedAckScheduledAckInterval(long optimizedAckScheduledAckInterval)
                                         throws JMSException
```
    Parameters:
    
    optimizedAckScheduledAckInterval - the optimizedAckScheduledAckInterval to set
    
    Throws:
    
    JMSException
  - hasMessageListener
```
public boolean hasMessageListener()
```
  - isConsumerExpiryCheckEnabled
```
public boolean isConsumerExpiryCheckEnabled()
```
  - setConsumerExpiryCheckEnabled
```
public void setConsumerExpiryCheckEnabled(boolean consumerExpiryCheckEnabled)
```

Class ActiveMQMessageConsumer

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

session

info

unconsumedMessages

deliveredMessages

Constructor Detail

ActiveMQMessageConsumer

Method Detail

getStats

getConsumerStats

getRedeliveryPolicy

setRedeliveryPolicy

getTransformer

setTransformer

getConsumerId

getConsumerName

isNoLocal

isBrowser

getDestination

getPrefetchNumber

isDurableSubscriber

getMessageSelector

getMessageListener

setMessageListener

getAvailableListener

setAvailableListener

receive

receive

receiveNoWait

close

dispose

checkClosed

sendPullCommand

checkMessageListener

setOptimizeAcknowledge

setPrefetchSize

acknowledge

commit

rollback

dispatch

getMessageSize

start

stop

toString

iterate

isInUse

getLastDeliveredSequenceId

getFailureError

setFailureError

getOptimizedAckScheduledAckInterval

setOptimizedAckScheduledAckInterval

hasMessageListener

isConsumerExpiryCheckEnabled

setConsumerExpiryCheckEnabled