de.erichseifert.gral.data

Class RowSubset

java.lang.Object

de.erichseifert.gral.data.AbstractDataSource

de.erichseifert.gral.data.RowSubset

All Implemented Interfaces:

DataListener, DataSource, java.io.Serializable, java.lang.Iterable<java.lang.Comparable<?>>

public abstract class RowSubset
extends AbstractDataSource
implements DataListener

Abstract class that represents a view on several rows of a data source. Implementations must implement the method accept(Row) which decides whether a specific row should be contained in this filtered data source.

Example that keeps only every second row:

 DataSource filtered = new RowSubset() {
     public boolean accept(Row row) {
         return row.getIndex()%2 == 0;
     }
 };
 

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
RowSubset(DataSource original) Creates a new instance with the specified data source.

Method Summary

Modifier and Type	Method and Description
abstract boolean	accept(Row row) Tests whether the specified row is accepted by this DataSubset or not.
void	dataAdded(DataSource source, DataChangeEvent... events) Method that is invoked when data has been added.
void	dataRemoved(DataSource source, DataChangeEvent... events) Method that is invoked when data has been removed.
void	dataUpdated(DataSource source, DataChangeEvent... events) Method that is invoked when data has been updated.
java.lang.Comparable<?>	get(int col, int row) Returns the row with the specified index.
int	getColumnCount() Returns the number of columns of the data source.
java.lang.Class<? extends java.lang.Comparable<?>>[]	getColumnTypes() Returns the data types of all columns.
Row	getRow(int row) Returns the row with the specified index.
int	getRowCount() Returns the number of rows of the data source.

Methods inherited from class de.erichseifert.gral.data.AbstractDataSource

addDataListener, getColumn, getColumnStatistics, getName, getRecord, getRowStatistics, getStatistics, isColumnNumeric, iterator, removeDataListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

RowSubset

public RowSubset(DataSource original)

Creates a new instance with the specified data source.

Parameters:

original - DataSource to be filtered.

Method Detail

getRow

public Row getRow(int row)

Description copied from class: AbstractDataSource

Returns the row with the specified index.

Specified by:

getRow in interface DataSource

Overrides:

getRow in class AbstractDataSource

Parameters:

row - Index of the row to return

Returns:

the Specified row of the data source

get

public java.lang.Comparable<?> get(int col,
                                   int row)

Returns the row with the specified index.

Specified by:

get in interface DataSource

Parameters:

col - index of the column to return

row - index of the row to return

Returns:

the specified value of the data cell

getColumnCount

public int getColumnCount()

Description copied from class: AbstractDataSource

Returns the number of columns of the data source.

Specified by:

getColumnCount in interface DataSource

Overrides:

getColumnCount in class AbstractDataSource

Returns:

number of columns in the data source.

getRowCount

public int getRowCount()

Returns the number of rows of the data source.

Specified by:

getRowCount in interface DataSource

Returns:

number of rows in the data source.

getColumnTypes

public java.lang.Class<? extends java.lang.Comparable<?>>[] getColumnTypes()

Description copied from class: AbstractDataSource

Returns the data types of all columns.

Specified by:

getColumnTypes in interface DataSource

Overrides:

getColumnTypes in class AbstractDataSource

Returns:

The data types of all column in the data source

dataAdded

public void dataAdded(DataSource source,
                      DataChangeEvent... events)

Method that is invoked when data has been added. This method is invoked by objects that provide support for DataListeners and should not be called manually.

Specified by:

dataAdded in interface DataListener

Parameters:

source - Data source that has been changed.

events - Optional event object describing the data values that have been added.

dataUpdated

public void dataUpdated(DataSource source,
                        DataChangeEvent... events)

Method that is invoked when data has been updated. This method is invoked by objects that provide support for DataListeners and should not be called manually.

Specified by:

dataUpdated in interface DataListener

Parameters:

source - Data source that has been changed.

events - Optional event object describing the data values that have been added

dataRemoved

public void dataRemoved(DataSource source,
                        DataChangeEvent... events)

Method that is invoked when data has been removed. This method is invoked by objects that provide support for DataListeners and should not be called manually.

Specified by:

dataRemoved in interface DataListener

Parameters:

source - Data source that has been changed.

events - Optional event object describing the data values that have been removed.

accept

public abstract boolean accept(Row row)

Tests whether the specified row is accepted by this DataSubset or not.

Parameters:

row - Row to be tested.

Returns:

True if the row should be kept.