```
@Retention(RUNTIME)
@Target(TYPE)
public @interface Plugin
```
Annotation identifying a plugin, which gets loaded by SciJava's dynamic discovery mechanism.

Author:

Curtis Rueden

See Also:

SciJavaPlugin, PluginService

Field Summary

Fields
Modifier and Type	Fields	Description
`static String`	`APPLICATION_MENU_ROOT`	Deprecated. Use `UIDetails.APPLICATION_MENU_ROOT` instead.
`static String`	`CONTEXT_MENU_ROOT`	Deprecated. Use a context-specific menu root string instead.

Required Element Summary

Required Elements
Modifier and Type Required Element Description

Class<? extends SciJavaPlugin> type
The type of plugin; e.g., Service.

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`Attr[]`	`attrs`	A list of additional attributes which can be used to extend this annotation beyond its built-in capabilities.
`String`	`description`	A longer description of the plugin (e.g., for use as a tool tip).
`boolean`	`enabled`	When false, the plugin is grayed out in the user interface, if applicable.
`boolean`	`headless`	Provides a "hint" as to whether the plugin would behave correctly in a headless context.
`String`	`iconPath`	Path to the plugin's icon (e.g., shown in the menu structure).
`String`	`initializer`	Defines a function that is called to initialize the plugin in some way.
`String`	`label`	The human-readable label to use (e.g., in the menu structure).
`Menu[]`	`menu`	Full menu path defining where the plugin is shown in the menu structure.
`String`	`menuPath`	Abbreviated menu path defining where the plugin is shown in the menu structure.
`String`	`menuRoot`	String identifier naming the menu to which this plugin belongs, or in the case of a tool, the context menu that should be displayed while the tool is active.
`String`	`name`	The name of the plugin.
`double`	`priority`	The plugin index returns plugins sorted by priority.
`boolean`	`selectable`	Whether the plugin can be selected in the user interface.
`String`	`selectionGroup`	For selectable plugins, specifies a name defining a group of linked plugins, only one of which is selected at any given time.
`boolean`	`visible`	When false, the plugin is not displayed in the user interface.

- Field Detail
  - APPLICATION_MENU_ROOT
```
@Deprecated
static final String APPLICATION_MENU_ROOT
```
    Deprecated.
    Use UIDetails.APPLICATION_MENU_ROOT instead.
- - CONTEXT_MENU_ROOT
```
@Deprecated
static final String CONTEXT_MENU_ROOT
```
    Deprecated.
    Use a context-specific menu root string instead. This one is too general. There is no such thing as a "default context menu" since such a thing wouldn't be a context menu!
- Element Detail
  - type
```
Class<? extends SciJavaPlugin> type
```
    The type of plugin; e.g., Service.
- - name
```
String name
```
    The name of the plugin.
    
    Default:
    
    ""
- - label
```
String label
```
    The human-readable label to use (e.g., in the menu structure).
    
    Default:
    
    ""
- - description
```
String description
```
    A longer description of the plugin (e.g., for use as a tool tip).
    
    Default:
    
    ""
- - menuPath
```
String menuPath
```
    Abbreviated menu path defining where the plugin is shown in the menu structure. Uses greater than signs (>) as a separator; e.g.: "Image > Overlay > Properties..." defines a "Properties..." menu item within the "Overlay" submenu of the "Image" menu. Use either menuPath() or menu() but not both.
    
    Default:
    
    ""
- - menu
```
Menu[] menu
```
    Full menu path defining where the plugin is shown in the menu structure. This construction allows menus to be fully specified including mnemonics, accelerators and icons. Use either menuPath() or menu() but not both.
    
    Default:
    
    {}
- - menuRoot
```
String menuRoot
```
    String identifier naming the menu to which this plugin belongs, or in the case of a tool, the context menu that should be displayed while the tool is active. The default value of UIDetails.APPLICATION_MENU_ROOT references the menu structure of the primary application window.
    
    Default:
    
    "app"
- - iconPath
```
String iconPath
```
    Path to the plugin's icon (e.g., shown in the menu structure).
    
    Default:
    
    ""
- - priority
```
double priority
```
    The plugin index returns plugins sorted by priority. For example, this is useful for Services to control which service implementation is chosen when multiple implementations are present in the classpath, as well as to force instantiation of one service over another when the dependency hierarchy does not dictate otherwise.
    Any double value is allowed, but for convenience, there are some presets:
    
    Priority.FIRST
    
    Priority.VERY_HIGH
    
    Priority.HIGH
    
    Priority.NORMAL
    
    Priority.LOW
    
    Priority.VERY_LOW
    
    Priority.LAST
    See Also:
    
    Service
    
    Default:
    
    0.0
- - selectable
```
boolean selectable
```
    Whether the plugin can be selected in the user interface. A plugin's selection state (if any) is typically rendered in the menu structure using a checkbox or radio button menu item (see selectionGroup()).
    
    Default:
    
    false
- - selectionGroup
```
String selectionGroup
```
    For selectable plugins, specifies a name defining a group of linked plugins, only one of which is selected at any given time. Typically this is rendered in the menu structure as a group of radio button menu items. If no group is given, the plugin is assumed to be a standalone toggle, and typically rendered as a checkbox menu item.
    
    Default:
    
    ""
- - enabled
```
boolean enabled
```
    When false, the plugin is grayed out in the user interface, if applicable.
    
    Default:
    
    true
- - visible
```
boolean visible
```
    When false, the plugin is not displayed in the user interface.
    
    Default:
    
    true
- - headless
```
boolean headless
```
    Provides a "hint" as to whether the plugin would behave correctly in a headless context.
    Plugin developers should not specify headless = true unless the plugin refrains from using any UI-specific features (e.g., AWT or Swing calls).
    
    Of course, merely setting this flag does not guarantee that the plugin will not invoke any headless-incompatible functionality, but it provides an extra safety net for downstream headless code that wishes to be conservative in which plugins it allows to execute.
    
    Default:
    
    false
- - initializer
```
String initializer
```
    Defines a function that is called to initialize the plugin in some way.
    
    Default:
    
    ""
- - attrs
```
Attr[] attrs
```
    A list of additional attributes which can be used to extend this annotation beyond its built-in capabilities.
    Note to developers: when designing new plugin types, it is tempting to use this attribute to store additional information about each plugin. However, we suggest doing so only if you need that additional information before creating an instance of the plugin: e.g., to decide whether to instantiate one, or even whether to load the annotated plugin class at all. If you are going to create a plugin instance anyway, it is cleaner and more type-safe to add proper API methods to the plugin type's interface reporting the same information.
    
    Default:
    
    {}

Annotation Type Plugin

Field Summary

Required Element Summary

Optional Element Summary

Field Detail

APPLICATION_MENU_ROOT

CONTEXT_MENU_ROOT

Element Detail

type

name

label

description

menuPath

menu

menuRoot

iconPath

priority

selectable

selectionGroup

enabled

visible

headless

initializer

attrs