jakarta.faces.model

Class ScalarDataModel<E>

java.lang.Object

jakarta.faces.model.DataModel<E>

jakarta.faces.model.ScalarDataModel<E>

All Implemented Interfaces:

Iterable<E>

public class ScalarDataModel<E>
extends DataModel<E>

ScalarDataModel is a convenience implementation of DataModel that wraps an individual Java object.

Constructor Summary

Constructors

Constructor and Description
ScalarDataModel() Construct a new ScalarDataModel with no specified wrapped data.
ScalarDataModel(E scalar) Construct a new ScalarDataModel wrapping the specified scalar object.

Method Summary

Modifier and Type	Method and Description
int	getRowCount() If there is wrappedData available, return 1.
E	getRowData() If wrapped data is available, return the wrapped data instance.
int	getRowIndex() Return the zero-relative index of the currently selected row.
Object	getWrappedData() Return the object representing the data wrapped by this DataModel, if any.
boolean	isRowAvailable() Return true if there is wrappedData available, and the current value of rowIndex is zero.
void	setRowIndex(int rowIndex) Set the zero-relative index of the currently selected row, or -1 to indicate that we are not positioned on a row.
void	setWrappedData(Object data) Set the object representing the data collection wrapped by this DataModel.

Methods inherited from class jakarta.faces.model.DataModel

addDataModelListener, getDataModelListeners, iterator, removeDataModelListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

ScalarDataModel

public ScalarDataModel()

Construct a new ScalarDataModel with no specified wrapped data.

ScalarDataModel

public ScalarDataModel(E scalar)

Construct a new ScalarDataModel wrapping the specified scalar object.

Parameters:

scalar - Scalar to be wrapped (if any)

Method Detail

isRowAvailable

public boolean isRowAvailable()

Return true if there is wrappedData available, and the current value of rowIndex is zero. Otherwise, return false.

Specified by:

isRowAvailable in class DataModel<E>

Returns:

true if and only if there is data available at the current index, false otherwise.

Throws:

FacesException - if an error occurs getting the row availability

getRowCount

public int getRowCount()

If there is wrappedData available, return 1. If no wrappedData is available, return -1.

Specified by:

getRowCount in class DataModel<E>

Returns:

the number of rows of data represented by this DataModel

Throws:

FacesException - if an error occurs getting the row count

getRowData

public E getRowData()

If wrapped data is available, return the wrapped data instance. Otherwise, return null.

Specified by:

getRowData in class DataModel<E>

Returns:

an object representing the data for the currently selected row index

Throws:

FacesException - if an error occurs getting the row data

IllegalArgumentException - if now row data is available at the currently specified row index

getRowIndex

public int getRowIndex()

Description copied from class: DataModel

Return the zero-relative index of the currently selected row. If we are not currently positioned on a row, or no wrappedData is available, return -1.

Specified by:

getRowIndex in class DataModel<E>

Returns:

the index of the currently selected row

Throws:

FacesException - if an error occurs getting the row index

setRowIndex

public void setRowIndex(int rowIndex)

Description copied from class: DataModel

Set the zero-relative index of the currently selected row, or -1 to indicate that we are not positioned on a row. It is possible to set the row index at a value for which the underlying data collection does not contain any row data. Therefore, callers may use the isRowAvailable() method to detect whether row data will be available for use by the getRowData() method.

If there is no wrappedData available when this method is called, the specified rowIndex is stored (and may be retrieved by a subsequent call to getRowData()), but no event is sent. Otherwise, if the currently selected row index is changed by this call, a DataModelEvent will be sent to the rowSelected() method of all registered DataModelListeners.

Specified by:

setRowIndex in class DataModel<E>

Parameters:

rowIndex - The new zero-relative index (must be non-negative)

Throws:

FacesException - if an error occurs setting the row index

IllegalArgumentException - if rowIndex is less than -1

getWrappedData

public Object getWrappedData()

Description copied from class: DataModel

Return the object representing the data wrapped by this DataModel, if any.

Specified by:

getWrappedData in class DataModel<E>

Returns:

the Object that this model wraps.

setWrappedData

public void setWrappedData(Object data)

Description copied from class: DataModel

Set the object representing the data collection wrapped by this DataModel. If the specified data is null, detach this DataModel from any previously wrapped data collection instead.

If data is non-null, the currently selected row index must be set to zero, and a DataModelEvent must be sent to the rowSelected() method of all registered DataModelListeners indicating that this row is now selected.

Specified by:

setWrappedData in class DataModel<E>

Parameters:

data - Data collection to be wrapped, or null to detach from any previous data collection

Throws:

ClassCastException - if data is not of the appropriate type for this DataModel implementation