org.jhotdraw.draw
Class AttributeKey<T>

java.lang.Object
  org.jhotdraw.draw.AttributeKey<T>

public class AttributeKey<T>
extends java.lang.Object

AttributeKey provides typesafe access to figure attributes.

An AttributeKey has a name, a type and a default value. The default value is returned by Figure.getAttribute, if a Figure does not have an attribute of the specified key.

The following code example shows how to basicSet and get an attribute on a Figure.

 Figure aFigure;
 AttributeKeys.STROKE_COLOR.set(aFigure, Color.blue);
 

See AttributeKeys for a list of useful attribute keys.

Version:

2.0.1 2008-02-13 Fixed comments. Removed equals and hashCode.
2.0 2007-05-12 Removed basicSet methods.
1.2 2007-04-10 Convenience methods for getting and setting a clone of an attribute added.
1.1 2006-12-29 Support for getting/setting attribute keys on a Map added.
1.0.1 2006-07-14 Null values are not returned anymore when null values are not allowed.
1.0 7. Juni 2006 Created.

Author:

Werner Randelshofer

Constructor Summary

AttributeKey(java.lang.String key)
Creates a new instance.

AttributeKey(java.lang.String key, T defaultValue)

AttributeKey(java.lang.String key, T defaultValue, boolean isNullValueAllowed)

Method Summary

void	basicSet(Figure f, T value) Sets a value on the specified figure without invoking willChange and changed on the figure.
void	basicSetClone(Figure f, T value) Sets a clone of a value on the specified figure, without invoking willChange and changed on the figure.
T	get(Figure f) Gets the value of the attribute denoted by this AttributeKey from a Figure.
T	get(java.util.Map<AttributeKey,java.lang.Object> a) Gets the value of the attribute denoted by this AttributeKey from a Map.
T	getClone(Figure f) Gets a clone of the value from the Figure.
T	getDefaultValue()
java.lang.String	getKey()
boolean	isAssignable(java.lang.Object value)
boolean	isNullValueAllowed()
void	set(Figure f, T value) Convenience method for setting a value on the specified figure and calling willChange before and changed after setting the value.
void	set(java.util.Map<AttributeKey,java.lang.Object> a, T value)
void	setClone(Figure f, T value) Convenience method for seting a clone of a value on the specified figure and calling willChange before and changed after setting the value.
void	setClone(java.util.Map<AttributeKey,java.lang.Object> a, T value) Sets a clone of the value to the Figure without firing events.
javax.swing.undo.UndoableEdit	setUndoable(Figure figure, T value, ResourceBundleUtil labels) Sets the attribute and returns an UndoableEditEvent which can be used to undo it.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

AttributeKey

public AttributeKey(java.lang.String key)

Creates a new instance.

AttributeKey

public AttributeKey(java.lang.String key,
                    T defaultValue)

AttributeKey

public AttributeKey(java.lang.String key,
                    T defaultValue,
                    boolean isNullValueAllowed)

Method Detail

getKey

public java.lang.String getKey()

getDefaultValue

public T getDefaultValue()

getClone

public T getClone(Figure f)

Gets a clone of the value from the Figure.

get

public T get(Figure f)

Gets the value of the attribute denoted by this AttributeKey from a Figure.

Parameters:

f - A figure.

Returns:

The value of the attribute.

get

public T get(java.util.Map<AttributeKey,java.lang.Object> a)

Gets the value of the attribute denoted by this AttributeKey from a Map.

Parameters:

a - A Map.

Returns:

The value of the attribute.

set

public void set(Figure f,
                T value)

Convenience method for setting a value on the specified figure and calling willChange before and changed after setting the value.

Parameters:

f - the Figure

value - the attribute value

basicSet

public void basicSet(Figure f,
                     T value)

Sets a value on the specified figure without invoking willChange and changed on the figure.

This method can be used to efficiently build a drawing from an InputFormat.

Parameters:

f - the Figure

value - the attribute value

setUndoable

public javax.swing.undo.UndoableEdit setUndoable(Figure figure,
                                                 T value,
                                                 ResourceBundleUtil labels)

Sets the attribute and returns an UndoableEditEvent which can be used to undo it.

setClone

public void setClone(Figure f,
                     T value)

Convenience method for seting a clone of a value on the specified figure and calling willChange before and changed after setting the value.

Parameters:

f - the Figure

value - the attribute value

basicSetClone

public void basicSetClone(Figure f,
                          T value)

Sets a clone of a value on the specified figure, without invoking willChange and changed on the figure.

This method can be used to efficiently build a drawing from an InputFormat.

Parameters:

f - the Figure

value - the attribute value

set

public void set(java.util.Map<AttributeKey,java.lang.Object> a,
                T value)

setClone

public void setClone(java.util.Map<AttributeKey,java.lang.Object> a,
                     T value)

Sets a clone of the value to the Figure without firing events.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

isNullValueAllowed

public boolean isNullValueAllowed()

isAssignable

public boolean isAssignable(java.lang.Object value)