uk.org.ogsadai.service.resource
Class DataServiceResource

java.lang.Object
  |
  +--uk.org.ogsadai.service.resource.DataServiceResource

public class DataServiceResource

extends java.lang.Object

A data service resource class.

Manages the interaction between the presentation (service) layer and the core (engine) layer in OGSA-DAI.

A data service resource includes a data resource accessor (used to access any underlying data resource) and an OGSA-DAI engine (as represented by a uk.org.ogsadai.engine.engine).

Author:

The OGSA-DAI Project Team

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

Copyright statement

See Also:

Constant Field Values

LOG

private static DAILogger LOG

Logger object for logging in this class

mID

private java.lang.Object mID

Data service resource ID

mProperties

private Properties mProperties

Data service resource properties

mSessionStreamManager

private final SessionStreamManager mSessionStreamManager

Session stream manager

mActivityFactory

private final ActivityFactory mActivityFactory

Factory for creating activities supported by the resource

mDataResourceAccessor

private final DataResourceAccessor mDataResourceAccessor

Manages access to data resource for the data service resource

mSessionCoordinator

private final SessionCoordinator mSessionCoordinator

Manages joining/releasing requests to/from sessions

mRequestFactory

private final RequestFactory mRequestFactory

Factory to create requests from perform documents

mEngine

private Engine mEngine

Request execution engine

mEngineConfiguration

private EngineConfiguration mEngineConfiguration

Request execution engine configuration

DataServiceResource

public DataServiceResource(java.lang.Object?id,
                           ActivitiesConfig?activitiesConfig,
                           DataResourceAccessor?dataResourceAccessor,
                           SessionComponentFactory?sessionComponentFactory,
                           ConcurrencySettings?concurrencySettings,
                           AccessAuthorizer?accessAuthorizer)
                    throws ResourceCreationException

Create a new data service resource.

Parameters:

id - Resource ID.

activitiesConfig - Details of the activities associated with the data service resource.

dataResourceAccessor - The data resource acccessor that gives access to any underlying data resource.

sessionComponentFactory - A factory to create the session components to be used by the data service resource.

concurrencySettings - Default concurrency settings for the resource.

accessAuthorizer - Grants or denies access to activites.

Throws:

java.lang.IllegalArgumentException - If any of the arguments is null or the id "".

ResourceCreationException - If the data service resource cannot be created for some reason.

addProperties

private void addProperties()

Adds all the properties associated with the data resource accessor and activity factory to the properties of the resource.

getID

public java.lang.Object getID()

Gets the resource ID.

Returns:

the resource ID.

getProperties

public Properties getProperties()

Gets the data service resource properties for the resource.

Returns:

the properties.

getSessionStreamManager

public SessionStreamManager getSessionStreamManager()

Gets the session stream manager for the resource.

Returns:

the session stream manager.

perform

public org.w3c.dom.Document perform(org.w3c.dom.Document?performDocument,
                                    RequestContext?requestContext)
                             throws ResourceRequestAuthorizationException,
                                    ResourceRequestSpecificationException,
                                    ResourceRequestExecutionException

Execute a perform document.

Parameters:

performDocument - The perform document.

requestContext - Information about the client and the request e.g. client security credentials.

Returns:

response document describing the status and possibly the results of the request.

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unsupported activity or a query expression is has incorrect syntax.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource e.g. a database connection disappears or a file is corrupted.

terminate

public void terminate()
               throws ResourceRequestAuthorizationException,
                      ResourceRequestSpecificationException,
                      ResourceRequestExecutionException

Terminate a current request.

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. the session to which the request belongs does not exist.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

getFully

public java.lang.Object getFully(SessionStreamID?id)
                          throws ResourceRequestAuthorizationException,
                                 ResourceRequestExecutionException,
                                 ResourceRequestSpecificationException

Get all the data from an output stream of a session.

Parameters:

id - Session and stream identifier.

Returns:

data

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unknown session or stream.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

See Also:

SessionStreamManager.getFully(uk.org.ogsadai.sessions.SessionStreamID)

getNBlocks

public java.lang.Object getNBlocks(SessionStreamID?id,
                                   int?numberOfBlocks)
                            throws ResourceRequestAuthorizationException,
                                   ResourceRequestExecutionException,
                                   ResourceRequestSpecificationException

Get a specific number of blocks of data from an output stream of a session.

Parameters:

id - Session and stream identifier.

numberOfBlocks - Number of blocks to get.

Returns:

data

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unknown session or stream.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

See Also:

SessionStreamManager.getNBlocks(uk.org.ogsadai.sessions.SessionStreamID, int)

getBlock

public java.lang.Object getBlock(SessionStreamID?id)
                          throws ResourceRequestAuthorizationException,
                                 ResourceRequestExecutionException,
                                 ResourceRequestSpecificationException

Get one block of data from an output stream of a session.

Parameters:

id - Session and stream identifier.

Returns:

data

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unknown session or stream.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

See Also:

SessionStreamManager.getNBlocks(uk.org.ogsadai.sessions.SessionStreamID, int)

putBlock

public void putBlock(SessionStreamID?id,
                     java.lang.Object?data)
              throws ResourceRequestAuthorizationException,
                     ResourceRequestExecutionException,
                     ResourceRequestSpecificationException

Put a block of data onto an input stream of a session.

Parameters:

id - Session and stream identifier.

data - Single block of data.

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unknown session or stream or the stream was closed.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

See Also:

SessionStreamManager.putBlock(uk.org.ogsadai.sessions.SessionStreamID, java.lang.Object)

putFully

public void putFully(SessionStreamID?id,
                     java.lang.Object?data)
              throws ResourceRequestAuthorizationException,
                     ResourceRequestExecutionException,
                     ResourceRequestSpecificationException

Put a complete set of data onto an input stream of a session.

Parameters:

id - Session and stream identifier.

data - Single block of data.

Throws:

ResourceRequestAuthorizationException - if the request fails because of an authorization problem.

ResourceRequestSpecificationException - if the request fails to execute due to a problem in the request e.g. it specifies an unknown session or stream or the stream was closed.

ResourceRequestExecutionException - if the request fails to execute due to a problem in the resource.

See Also:

SessionStreamManager.putFully(uk.org.ogsadai.sessions.SessionStreamID, java.lang.Object)