uk.org.ogsadai.engine.controlflow
Class CompositeRequestComponent

java.lang.Object
  |
  +--uk.org.ogsadai.engine.controlflow.CompositeRequestComponent

All Implemented Interfaces:

RequestComponent

Direct Known Subclasses:

FlowRequestComponent, SequenceRequestComponent

public abstract class CompositeRequestComponent

extends java.lang.Object

implements RequestComponent

A CompositeRequestComponent is a RequestComponent that may contain child components. The iterator method is defined to provide access to these children for a concrete implementation.

Author:

The OGSA-DAI Project Team

Field Summary

private static java.lang.String	COPYRIGHT_NOTICE Copyright statement
private static DAILogger	LOG Logger object for logging in this class
private java.util.List	mChildren The child components.

Constructor Summary

CompositeRequestComponent()

Method Summary

void	add(RequestComponent child) Adds a child to a composite component.
java.util.List	children() Returns a non-mutable list of the children of this RequestComponent.
boolean	generatesResultData() Indicates whether or not this component will generate any result data.
void	initialise(ActivityContext context, Session session, ResponseBuilder responseBuilder) Initialises the component.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface uk.org.ogsadai.engine.controlflow.RequestComponent

process, terminate

Field Detail

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

Copyright statement

See Also:

Constant Field Values

LOG

private static final DAILogger LOG

Logger object for logging in this class

mChildren

private final java.util.List mChildren

The child components.

Constructor Detail

CompositeRequestComponent

public CompositeRequestComponent()

Method Detail

add

public void add(RequestComponent child)

Description copied from interface: RequestComponent

Adds a child to a composite component. Note that an empty implementation of this method should be provided for any leaf components.

Specified by:

add in interface RequestComponent

Parameters:

child - The child RequestComponent

children

public java.util.List children()

Description copied from interface: RequestComponent

Returns a non-mutable list of the children of this RequestComponent. If this component is a leaf and not a composite then java.util.Collections.EMPTY_LIST should be returned.

Specified by:

children in interface RequestComponent

Returns:

a java.util.List containing any children.

initialise

public void initialise(ActivityContext context,
                       Session session,
                       ResponseBuilder responseBuilder)
                throws RequestSpecificationException,
                       RequestExecutionException

Description copied from interface: RequestComponent

Initialises the component. After this method has been returned the generatesResultData method must operational.

Specified by:

initialise in interface RequestComponent

Parameters:

context - The context for the request

session - The session for the request

responseBuilder - The response builder for assembling the response document

Throws:

RequestSpecificationException - If there is an initialisation problem caused by incorrect information in the request.

RequestExecutionException - If a problem occurs during initialisation that is not caused by incorrect information in the request.

generatesResultData

public boolean generatesResultData()

Description copied from interface: RequestComponent

Indicates whether or not this component will generate any result data. This can only be invoked after the initialise method has returned. This method is used by the engine to determine whether to process a request synchronously or asynchronously.

Specified by:

generatesResultData in interface RequestComponent

Returns:

true if so, false otherwise