org.pentaho.reporting.engine.classic.core.filter
Class EmptyDataSource

java.lang.Object
  org.pentaho.reporting.engine.classic.core.filter.EmptyDataSource

All Implemented Interfaces:

Serializable, Cloneable, DataSource

public final class EmptyDataSource
extends Object
implements DataSource

A data source that always returns null.

Author:

Thomas Morgner

See Also:

Serialized Form

Constructor Summary

EmptyDataSource()
Default-Constructor.

Method Summary

Object	clone() Clones the data source.
Object	getValue(ExpressionRuntime runtime, Element element) Returns the value for the data source (always null in this case).

Methods inherited from class java.lang.Object

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

Constructor Detail

EmptyDataSource

public EmptyDataSource()

Default-Constructor.

Method Detail

getValue

public Object getValue(ExpressionRuntime runtime,
                       Element element)

Returns the value for the data source (always null in this case).

Specified by:

getValue in interface DataSource

Parameters:

runtime - the expression runtime that is used to evaluate formulas and expressions when computing the value of this filter.

element -

Returns:

always null.

clone

public Object clone()

Clones the data source.

Specified by:

clone in interface DataSource

Overrides:

clone in class Object

Returns:

a clone.