Eclipse Platform
Release 3.0

org.eclipse.ui.commands
Interface ICategory

All Superinterfaces:
Comparable

public interface ICategory
extends Comparable

A category is a grouping of commands by functional area. For example, in the Eclipse workbench, "Text Editing" is a category containing various commands related to text editing. A category's primary functionality is to control the display of commands to the user. When appropriate, commands displayed to the user (e.g., keys preference page) will be grouped by category.

An instance of ICategory is a handle representing a category as defined by the extension point org.eclipse.ui.commands. The identifier of the handle is identifier of the category being represented.

An instance of ICategory can be obtained from an instance of ICommandManager for any identifier, whether or not a category with that identifier defined in the plugin registry.

The handle-based nature of this API allows it to work well with runtime plugin activation and deactivation, which causes dynamic changes to the plugin registry, and therefore, potentially, dynamic changes to the set of category definitions.

This interface is not intended to be extended or implemented by clients.

Since:
3.0
See Also:
ICategoryListener, ICommandManager

Method Summary
 void addCategoryListener(ICategoryListener categoryListener)
          Registers an instance of ICategoryListener to listen for changes to attributes of this instance.
 String getDescription()
           Returns the description of the category represented by this handle, suitable for display to the user.
 String getId()
          Returns the identifier of this handle.
 String getName()
           Returns the name of the category represented by this handle, suitable for display to the user.
 boolean isDefined()
           Returns whether or not the category represented by this handle is defined.
 void removeCategoryListener(ICategoryListener categoryListener)
          Unregisters an instance of ICategoryListener listening for changes to attributes of this instance.
 
Methods inherited from interface java.lang.Comparable
compareTo
 

Method Detail

addCategoryListener

public void addCategoryListener(ICategoryListener categoryListener)
Registers an instance of ICategoryListener to listen for changes to attributes of this instance.

Parameters:
categoryListener - the instance of ICategoryListener to register. Must not be null. If an attempt is made to register an instance of ICategoryListener which is already registered with this instance, no operation is performed.

getDescription

public String getDescription()
                      throws NotDefinedException

Returns the description of the category represented by this handle, suitable for display to the user.

Notification is sent to all registered listeners if this attribute changes.

Returns:
the description of the category represented by this handle. Guaranteed not to be null.
Throws:
NotDefinedException - if the category represented by this handle is not defined.

getId

public String getId()
Returns the identifier of this handle.

Returns:
the identifier of this handle. Guaranteed not to be null.

getName

public String getName()
               throws NotDefinedException

Returns the name of the category represented by this handle, suitable for display to the user.

Notification is sent to all registered listeners if this attribute changes.

Returns:
the name of the category represented by this handle. Guaranteed not to be null.
Throws:
NotDefinedException - if the category represented by this handle is not defined.

isDefined

public boolean isDefined()

Returns whether or not the category represented by this handle is defined.

Notification is sent to all registered listeners if this attribute changes.

Returns:
true, iff the category represented by this handle is defined.

removeCategoryListener

public void removeCategoryListener(ICategoryListener categoryListener)
Unregisters an instance of ICategoryListener listening for changes to attributes of this instance.

Parameters:
categoryListener - the instance of ICategoryListener to unregister. Must not be null. If an attempt is made to unregister an instance of ICategoryListener which is not already registered with this instance, no operation is performed.

Eclipse Platform
Release 3.0

Guidelines for using Eclipse APIs.

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