org.jfree.report.flow.layoutprocessor

Class BufferingLayoutController

java.lang.Object

org.jfree.report.flow.layoutprocessor.AbstractLayoutController

org.jfree.report.flow.layoutprocessor.BufferingLayoutController

All Implemented Interfaces:

java.lang.Cloneable, LayoutController

public abstract class BufferingLayoutController
extends AbstractLayoutController

Todo: Document me!

Since:

05.03.2007

Author:

Thomas Morgner

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BufferingLayoutController()

Method Summary

Modifier and Type	Method and Description
LayoutController	advance(ReportTarget target) Advances the processing position.
java.lang.Object	clone() Creates a copy of this layout controller.
protected abstract LayoutController	getInitialDelegate()
void	initialize(java.lang.Object node, FlowController flowController, LayoutController parent) Initializes the layout controller.
boolean	isAdvanceable() Checks, whether the layout controller would be advanceable.
LayoutController	join(FlowController flowController) Joins with a delegated process flow.
protected LayoutController	joinWithParent() Joins the layout controller with the parent.

Methods inherited from class org.jfree.report.flow.layoutprocessor.AbstractLayoutController

createPrecomputeInstance, getFlowController, getNode, getParent, isInitialized

Methods inherited from class java.lang.Object

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

Constructor Detail

BufferingLayoutController

protected BufferingLayoutController()

Method Detail

advance

public LayoutController advance(ReportTarget target)
                         throws DataSourceException,
                                ReportDataFactoryException,
                                ReportProcessingException

Advances the processing position.

Parameters:

target - the report target that receives generated events.

Returns:

the new layout controller instance representing the new state.

Throws:

DataSourceException - if there was a problem reading data from the datasource.

ReportProcessingException - if there was a general problem during the report processing.

ReportDataFactoryException - if a query failed.

joinWithParent

protected LayoutController joinWithParent()
                                   throws ReportProcessingException,
                                          ReportDataFactoryException,
                                          DataSourceException

Joins the layout controller with the parent. This simply calls join(org.jfree.report.flow.FlowController) on the parent. A join operation is necessary to propagate changes in the flow-controller to the parent for further processing.

Returns:

the joined parent.

Throws:

java.lang.IllegalStateException - if this layout controller has no parent.

ReportProcessingException

ReportDataFactoryException

DataSourceException

initialize

public void initialize(java.lang.Object node,
                       FlowController flowController,
                       LayoutController parent)
                throws DataSourceException,
                       ReportDataFactoryException,
                       ReportProcessingException

Initializes the layout controller. This method is called exactly once. It is the creators responsibility to call this method.

Calling initialize after the first advance must result in a IllegalStateException.

Specified by:

initialize in interface LayoutController

Overrides:

initialize in class AbstractLayoutController

Parameters:

node - the currently processed object or layout node.

flowController - the current flow controller.

parent - the parent layout controller that was responsible for instantiating this controller.

Throws:

DataSourceException - if there was a problem reading data from the datasource.

ReportProcessingException - if there was a general problem during the report processing.

ReportDataFactoryException - if a query failed.

getInitialDelegate

protected abstract LayoutController getInitialDelegate()

isAdvanceable

public boolean isAdvanceable()

Description copied from interface: LayoutController

Checks, whether the layout controller would be advanceable. If this method returns true, it is generally safe to call the 'advance()' method.

Returns:

true, if the layout controller is advanceable, false otherwise.

join

public LayoutController join(FlowController flowController)
                      throws ReportProcessingException,
                             DataSourceException

Joins with a delegated process flow. This is generally called from a child flow and should *not* (I mean it!) be called from outside. If you do, you'll suffer.

Parameters:

flowController - the flow controller of the parent.

Returns:

the joined layout controller that incorperates all changes from the delegate.

Throws:

ReportProcessingException

DataSourceException

clone

public java.lang.Object clone()

Description copied from interface: LayoutController

Creates a copy of this layout controller.

Specified by:

clone in interface LayoutController

Overrides:

clone in class AbstractLayoutController

Returns:

a copy.