JHotDraw 7.4.1

org.jhotdraw.draw
Class AttributeKey<T>

java.lang.Object
  extended by org.jhotdraw.draw.AttributeKey<T>
All Implemented Interfaces:
java.io.Serializable

public class AttributeKey<T>
extends java.lang.Object
implements java.io.Serializable

An attribute key provides typesafe access to an attribute of a Figure.

An AttributeKey has a name, a type and a default value. The default value is returned by Figure.get, 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.put(aFigure, Color.blue);
 

See AttributeKeys for a list of useful attribute keys.

Version:
$Id: AttributeKey.java 604 2010-01-09 12:00:29Z rawcoder $
Author:
Werner Randelshofer
See Also:
Serialized Form

Constructor Summary
AttributeKey(java.lang.String key, java.lang.Class<T> clazz)
          Creates a new instance with the specified attribute key, type token class, default value null, and allowing null values.
AttributeKey(java.lang.String key, java.lang.Class<T> clazz, T defaultValue)
          Creates a new instance with the specified attribute key, type token class, and default value, and allowing null values.
AttributeKey(java.lang.String key, java.lang.Class<T> clazz, T defaultValue, boolean isNullValueAllowed)
          Creates a new instance with the specified attribute key, type token class, default value, and allowing or disallowing null values.
AttributeKey(java.lang.String key, java.lang.Class<T> clazz, T defaultValue, boolean isNullValueAllowed, ResourceBundleUtil labels)
          Creates a new instance with the specified attribute key, type token class, default value, and allowing or disallowing null values.
 
Method Summary
 boolean equals(java.lang.Object that)
           
 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()
          Returns the default value of the attribute.
 java.lang.String getKey()
          Returns the key string.
 java.lang.String getPresentationName()
          Returns a localized human friendly presentation of the key.
 int hashCode()
           
 boolean isAssignable(java.lang.Object value)
          Returns true if the specified value is assignable with this key.
 boolean isNullValueAllowed()
          Returns true if null values are allowed.
 T put(java.util.Map<AttributeKey,java.lang.Object> a, T value)
          Use this method to perform a type-safe put operation of an attribute into a Map.
 void putClone(java.util.Map<AttributeKey,java.lang.Object> a, T value)
          Convenience method for putting a clone of a value on a map.
 void set(Figure f, T value)
          Convenience method for setting a value on a Figure.
 void setClone(Figure f, T value)
          Convenience method for setting a clone of a value on a figure.
 javax.swing.undo.UndoableEdit setUndoable(Figure f, T value)
          Sets the attribute and returns an UndoableEditEvent which can be used to undo it.
 java.lang.String toString()
          Returns the key string.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

AttributeKey

public AttributeKey(java.lang.String key,
                    java.lang.Class<T> clazz)
Creates a new instance with the specified attribute key, type token class, default value null, and allowing null values.


AttributeKey

public AttributeKey(java.lang.String key,
                    java.lang.Class<T> clazz,
                    T defaultValue)
Creates a new instance with the specified attribute key, type token class, and default value, and allowing null values.


AttributeKey

public AttributeKey(java.lang.String key,
                    java.lang.Class<T> clazz,
                    T defaultValue,
                    boolean isNullValueAllowed)
Creates a new instance with the specified attribute key, type token class, default value, and allowing or disallowing null values.


AttributeKey

public AttributeKey(java.lang.String key,
                    java.lang.Class<T> clazz,
                    T defaultValue,
                    boolean isNullValueAllowed,
                    ResourceBundleUtil labels)
Creates a new instance with the specified attribute key, type token class, default value, and allowing or disallowing null values.

Parameters:
key - The key string.
clazz - This is used as a "type token" for assignability checks at runtime.
isNullValueAllowed - whether null values are allowed.
labels - ResourceBundle for human friendly representation of this attribute key. The ResourceBundle must have a property named "attribute." + key + ".text".
Method Detail

getKey

public java.lang.String getKey()
Returns the key string.

Returns:
key string.

getPresentationName

public java.lang.String getPresentationName()
Returns a localized human friendly presentation of the key.

Returns:
the presentation name of the key.

getDefaultValue

public T getDefaultValue()
Returns the default value of the attribute.

Returns:
the default value.

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 a Figure.

Note: Unlike in previous versions of JHotDraw 7, this method does not call f.willChange() before setting the value, and f.changed() afterwards.

Parameters:
f - the Figure
value - the attribute value

setUndoable

public javax.swing.undo.UndoableEdit setUndoable(Figure f,
                                                 T value)
Sets the attribute and returns an UndoableEditEvent which can be used to undo it.

Note: Unlike in previous versions of JHotDraw 7, this method does not call f.willChange() before setting the value, and f.changed() afterwards.


setClone

public void setClone(Figure f,
                     T value)
Convenience method for setting a clone of a value on a figure.

Note: Unlike in previous versions of JHotDraw 7, this method does not call f.willChange() before setting the value, and f.changed() afterwards.

Parameters:
f - the Figure
value - the attribute value

putClone

public void putClone(java.util.Map<AttributeKey,java.lang.Object> a,
                     T value)
Convenience method for putting a clone of a value on a map.

Parameters:
a - the map
value - the attribute value

put

public T put(java.util.Map<AttributeKey,java.lang.Object> a,
             T value)
Use this method to perform a type-safe put operation of an attribute into a Map.

Parameters:
a - An attribute map.
value - The new value.
Returns:
The old value.

isNullValueAllowed

public boolean isNullValueAllowed()
Returns true if null values are allowed.

Returns:
true if null values are allowed.

isAssignable

public boolean isAssignable(java.lang.Object value)
Returns true if the specified value is assignable with this key.

Parameters:
value -
Returns:
True if assignable.

toString

public java.lang.String toString()
Returns the key string.

Overrides:
toString in class java.lang.Object

hashCode

public int hashCode()
Overrides:
hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object that)
Overrides:
equals in class java.lang.Object

Copyright 1996-2010 (c) by the authors and contributors of the JHotDraw project.
Some rights reserved.