com.pcbsys.nirvana.client.nQueueReader Class Referenceabstract

This class is the base class for all Queue Readers and provides a generic reader interface. More...

Inheritance diagram for com.pcbsys.nirvana.client.nQueueReader:
com.pcbsys.nirvana.client.nQueueAsyncReader com.pcbsys.nirvana.client.nQueueSyncFragmentReader com.pcbsys.nirvana.client.nQueueSyncReader com.pcbsys.nirvana.client.nQueueAsyncTransactionReader com.pcbsys.nirvana.client.nQueueSyncTransactionFragmentReader com.pcbsys.nirvana.client.nQueueSyncTransactionReader

Public Member Functions

boolean hasConsumedEvents ()
 Method to see whether the reader has consumed any events. More...
 
boolean isClosed ()
 When a reader is closed, the physical subscription is closed at the server. More...
 
boolean isClosedLocally ()
 A reader can be closed, but the physical subscription queue is not closed at the server. More...
 
final nConsumeEvent[] peek (final nQueuePeekContext context) throws nSecurityException, nChannelNotFoundException, nSessionNotConnectedException, nRequestTimedOutException, nUnexpectedResponseException, nSessionPausedException, nIllegalArgumentException, nIllegalStateException
 Performs a non destructive read. More...
 

Static Public Member Functions

static nQueuePeekContext createContext ()
 Creates a Queue Peek Context, which is used to traverse the queue. More...
 
static nQueuePeekContext createContext (final int windowSize)
 Creates a Queue Peek Context, which is used to traverse the queue. More...
 
static nQueuePeekContext createContext (final int windowSize, final String selector)
 Creates a Queue Peek Context, which is used to traverse the queue. More...
 

Detailed Description

This class is the base class for all Queue Readers and provides a generic reader interface.

Member Function Documentation

static nQueuePeekContext com.pcbsys.nirvana.client.nQueueReader.createContext ( )
static

Creates a Queue Peek Context, which is used to traverse the queue.

Returns
A new nQueuePeekContext
static nQueuePeekContext com.pcbsys.nirvana.client.nQueueReader.createContext ( final int  windowSize)
static

Creates a Queue Peek Context, which is used to traverse the queue.

Parameters
windowSizeThe size of the window over the queue to uses
Returns
A new nQueuePeekContext
static nQueuePeekContext com.pcbsys.nirvana.client.nQueueReader.createContext ( final int  windowSize,
final String  selector 
)
static

Creates a Queue Peek Context, which is used to traverse the queue.

Parameters
windowSizeThe size of the window over the queue to uses
selectorA message selector to be applied on the events received
Returns
A new nQueuePeekContext
boolean com.pcbsys.nirvana.client.nQueueReader.hasConsumedEvents ( )

Method to see whether the reader has consumed any events.

For transactional readers, this is reset every time commit or rollback is called.

Returns
true if any events have been consumed by the reader
boolean com.pcbsys.nirvana.client.nQueueReader.isClosed ( )

When a reader is closed, the physical subscription is closed at the server.

For Transactional readers, a close will rollback to the last committed event.

Returns
true if the reader has been closed
boolean com.pcbsys.nirvana.client.nQueueReader.isClosedLocally ( )

A reader can be closed, but the physical subscription queue is not closed at the server.

For Transactional readers, a local close will not rollback to the last committed event.

Returns
true if the reader has been closed locally but not at the server

Performs a non destructive read.

Parameters
contextPeek Context to use. Used when multiple calls required to travers a queue
Returns
An Array of events
Exceptions
nSecurityExceptionIf the client is not authorized to perform this request
nChannelNotFoundExceptionThe queue was not found
nSessionNotConnectedExceptionClient is not currently connected to the server
nRequestTimedOutExceptionThe server did not respond within the timeout
nUnexpectedResponseExceptionThe server responded with an unexpected response
nIllegalArgumentExceptionInvalid parameters passed
nSessionPausedExceptionThe session is currently paused, please resume
nIllegalStateExceptionThis exception is raised if there is any issues with any of the arguments used by this method. One condition of this is if this object has been invalidated and no longer can be utilised, this can occur if a delete request has been issued to the connected server.