org.jfree.data.general

Class AbstractDataset

java.lang.Object

org.jfree.data.general.AbstractDataset

All Implemented Interfaces:

java.io.ObjectInputValidation, java.io.Serializable, java.lang.Cloneable, Dataset

Direct Known Subclasses:

AbstractSeriesDataset, CategoryToPieDataset, DefaultBoxAndWhiskerCategoryDataset, DefaultCategoryDataset, DefaultHeatMapDataset, DefaultKeyedValueDataset, DefaultMultiValueCategoryDataset, DefaultPieDataset, DefaultStatisticalCategoryDataset, DefaultValueDataset, SlidingCategoryDataset, SlidingGanttCategoryDataset, WaferMapDataset

public abstract class AbstractDataset
extends java.lang.Object
implements Dataset, java.lang.Cloneable, java.io.Serializable, java.io.ObjectInputValidation

An abstract implementation of the Dataset interface, containing a mechanism for registering change listeners.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private DatasetGroup	group The group that the dataset belongs to.
private javax.swing.event.EventListenerList	listenerList Storage for registered change listeners.
private boolean	notify A flag that can be used to temporarily suppress dataset change event notifications.
private static long	serialVersionUID For serialization.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractDataset() Constructs a dataset.

Method Summary

Modifier and Type	Method and Description
void	addChangeListener(DatasetChangeListener listener) Registers an object to receive notification of changes to the dataset.
java.lang.Object	clone() Returns a clone of the dataset.
protected void	fireDatasetChanged() Notifies all registered listeners that the dataset has changed, provided that the notify flag has not been set to false.
DatasetGroup	getGroup() Returns the dataset group for the dataset.
boolean	getNotify() Returns the value of the notify flag.
boolean	hasListener(java.util.EventListener listener) Returns true if the specified object is registered with the dataset as a listener.
protected void	notifyListeners(DatasetChangeEvent event) Notifies all registered listeners that the dataset has changed.
private void	readObject(java.io.ObjectInputStream stream) Restores a serialized object.
void	removeChangeListener(DatasetChangeListener listener) Deregisters an object so that it no longer receives notification of changes to the dataset.
void	setGroup(DatasetGroup group) Sets the dataset group for the dataset.
void	setNotify(boolean notify) Sets the notify flag, which controls whether or not the fireDatasetChanged() method notifies listeners.
void	validateObject() Validates the object.
private void	writeObject(java.io.ObjectOutputStream stream) Handles serialization.

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

For serialization.

See Also:

Constant Field Values

group

private DatasetGroup group

The group that the dataset belongs to.

listenerList

private transient javax.swing.event.EventListenerList listenerList

Storage for registered change listeners.

notify

private boolean notify

A flag that can be used to temporarily suppress dataset change event notifications.

Constructor Detail

AbstractDataset

protected AbstractDataset()

Constructs a dataset. By default, the dataset is assigned to its own group.

Method Detail

getGroup

public DatasetGroup getGroup()

Returns the dataset group for the dataset.

Specified by:

getGroup in interface Dataset

Returns:

The group (never null).

See Also:

setGroup(DatasetGroup)

setGroup

public void setGroup(DatasetGroup group)

Sets the dataset group for the dataset.

Specified by:

setGroup in interface Dataset

Parameters:

group - the group (null not permitted).

See Also:

getGroup()

getNotify

public boolean getNotify()

Returns the value of the notify flag. The default value is true. If this is false, calls to the fireDatasetChanged() method will NOT trigger a dataset change event.

Returns:

A boolean.

Since:

1.0.17

setNotify

public void setNotify(boolean notify)

Sets the notify flag, which controls whether or not the fireDatasetChanged() method notifies listeners. Setting this flag to true will trigger a DatasetChangeEvent because there may be queued up changes.

Parameters:

notify - the new flag value.

Since:

1.0.17

addChangeListener

public void addChangeListener(DatasetChangeListener listener)

Registers an object to receive notification of changes to the dataset.

Specified by:

addChangeListener in interface Dataset

Parameters:

listener - the object to register.

See Also:

removeChangeListener(DatasetChangeListener)

removeChangeListener

public void removeChangeListener(DatasetChangeListener listener)

Deregisters an object so that it no longer receives notification of changes to the dataset.

Specified by:

removeChangeListener in interface Dataset

Parameters:

listener - the object to deregister.

See Also:

addChangeListener(DatasetChangeListener)

hasListener

public boolean hasListener(java.util.EventListener listener)

Returns true if the specified object is registered with the dataset as a listener. Most applications won't need to call this method, it exists mainly for use by unit testing code.

Parameters:

listener - the listener.

Returns:

A boolean.

See Also:

addChangeListener(DatasetChangeListener), removeChangeListener(DatasetChangeListener)

fireDatasetChanged

protected void fireDatasetChanged()

Notifies all registered listeners that the dataset has changed, provided that the notify flag has not been set to false.

See Also:

addChangeListener(DatasetChangeListener)

notifyListeners

protected void notifyListeners(DatasetChangeEvent event)

Notifies all registered listeners that the dataset has changed.

Parameters:

event - contains information about the event that triggered the notification.

See Also:

addChangeListener(DatasetChangeListener), removeChangeListener(DatasetChangeListener)

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Returns a clone of the dataset. The cloned dataset will NOT include the DatasetChangeListener references that have been registered with this dataset.

Overrides:

clone in class java.lang.Object

Returns:

A clone.

Throws:

java.lang.CloneNotSupportedException - if the dataset does not support cloning.

writeObject

private void writeObject(java.io.ObjectOutputStream stream)
                  throws java.io.IOException

Handles serialization.

Parameters:

stream - the output stream.

Throws:

java.io.IOException - if there is an I/O problem.

readObject

private void readObject(java.io.ObjectInputStream stream)
                 throws java.io.IOException,
                        java.lang.ClassNotFoundException

Restores a serialized object.

Parameters:

stream - the input stream.

Throws:

java.io.IOException - if there is an I/O problem.

java.lang.ClassNotFoundException - if there is a problem loading a class.

validateObject

public void validateObject()
                    throws java.io.InvalidObjectException

Validates the object. We use this opportunity to call listeners who have registered during the deserialization process, as listeners are not serialized. This method is called by the serialization system after the entire graph is read. This object has registered itself to the system with a priority of 10. Other callbacks may register with a higher priority number to be called before this object, or with a lower priority number to be called after the listeners were notified. All listeners are supposed to have register by now, either in their readObject or validateObject methods. Notify them that this dataset has changed.

Specified by:

validateObject in interface java.io.ObjectInputValidation

Throws:

java.io.InvalidObjectException - If the object cannot validate itself.