oracle.cabo.ui.data.provider
Class DefaultingDataProvider

java.lang.Object
  |
  +--oracle.cabo.ui.data.provider.DefaultingDataProvider

All Implemented Interfaces:

DataProvider

public class DefaultingDataProvider

extends java.lang.Object

implements DataProvider

DataProvider that joins two other data providers, using the second only if the first cannot provide a DataObject.

Constructor Summary

DefaultingDataProvider(DataProvider first, DataProvider second)
Creates a DefaultingDataProvider.

Method Summary

void	cleanup(RenderingContext context) RenderingContext implementations must call cleanup() once after the last callto getDataObject().
DataObject	getDataObject(RenderingContext cntxt, java.lang.String namespace, java.lang.String name) Returns the data object if the namespace and name are an exact match.
void	init(RenderingContext context) RenderingContext implementations must call init() once before calling getDataObject().

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultingDataProvider

public DefaultingDataProvider(DataProvider first,
                              DataProvider second)

Creates a DefaultingDataProvider.

Parameters:

first - the primary data provider

second - the secondary data provider, used only if calls to the first fail

Method Detail

getDataObject

public DataObject getDataObject(RenderingContext cntxt,
                                java.lang.String namespace,
                                java.lang.String name)

Returns the data object if the namespace and name are an exact match.

Specified by:

getDataObject in interface DataProvider

Following copied from interface: oracle.cabo.ui.data.DataProvider

Parameters:

context - the current rendering context

namespace - the namespace of the requested DataObject

name - the name of the requested DataObject

Returns:

the DataObject for the specified namespace and name, or null if no such dataObject exists.

init

public void init(RenderingContext context)

RenderingContext implementations must call init() once before calling getDataObject(). In general, they should try to call it as early as possible.

Specified by:

init in interface DataProvider

cleanup

public void cleanup(RenderingContext context)

RenderingContext implementations must call cleanup() once after the last callto getDataObject().

Specified by:

cleanup in interface DataProvider