org.jfree.report.flow.layoutprocessor
Interface LayoutController

All Superinterfaces:
java.lang.Cloneable
All Known Implementing Classes:
AbstractLayoutController, AutoTableItemLayoutController, AutoTableLayoutController, BufferingLayoutController, ContentElementLayoutController, ElementLayoutController, ReportLayoutController, SectionLayoutController, StaticTextLayoutController, SubReportLayoutController

public interface LayoutController
extends java.lang.Cloneable

The layout controller iterates over the report layout. It uses a flow controller to query the data.

Author:
Thomas Morgner

Method Summary
 LayoutController advance(ReportTarget target)
          Advances the processing position.
 java.lang.Object clone()
          Creates a copy of this layout controller.
 LayoutController createPrecomputeInstance(FlowController fc)
          Derives a copy of this controller that is suitable to perform a precomputation.
 FlowController getFlowController()
           
 java.lang.Object getNode()
           
 LayoutController getParent()
          Retrieves the parent of this layout controller.
 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.
 

Method Detail

getParent

LayoutController getParent()
Retrieves the parent of this layout controller. This allows childs to query their context.

Returns:
the layout controller's parent to null if there is no parent.

initialize

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.

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.

advance

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.

isAdvanceable

boolean isAdvanceable()
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

LayoutController join(FlowController flowController)
                      throws DataSourceException,
                             ReportDataFactoryException,
                             ReportProcessingException
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:
DataSourceException
ReportDataFactoryException
ReportProcessingException

clone

java.lang.Object clone()
Creates a copy of this layout controller.

Returns:
a copy.

createPrecomputeInstance

LayoutController createPrecomputeInstance(FlowController fc)
Derives a copy of this controller that is suitable to perform a precomputation. The returned layout controller must be independent from the it's anchestor controller.

Parameters:
fc - a new flow controller for the precomputation.
Returns:
a copy that is suitable for precomputation.

getFlowController

FlowController getFlowController()

getNode

java.lang.Object getNode()