Extensions are the most common way for a plugin to extend the Consulo Platform's functionality in a way that is not as straightforward as adding an action to a menu or toolbar.

Extensions are implemented by annotating classes with @ExtensionImpl that extend or implement interfaces annotated with @ExtensionAPI. The following are some of the most common tasks accomplished using extensions:

• Tool window extensions allow plugins to add tool windows (panels displayed at the sides of the IDE user interface);
• Configurable extensions allow plugins to add pages to the Settings/Preferences dialog;
• Custom language plugins use many extension points to extend various language support features in the IDE.

There are more than 1000 extension points available in the platform and the bundled plugins, allowing to customize different parts of the IDE behavior.

Declaring Extensions

To declare an extension in your plugin:

1. Find the base interface or abstract class annotated with @ExtensionAPI(ComponentScope.xxx) that represents the extension point you want to implement.
2. Create a class that extends or implements it.
3. Annotate your class with @ExtensionImpl.

For example, if you want to provide a parser for a custom language, the platform defines the extension point as follows:

// The platform defines the extension point:
@ExtensionAPI(ComponentScope.APPLICATION)
public interface ParserDefinition extends LanguageExtension { ... }

// Your plugin implements it:
@ExtensionImpl
public class MyParserDefinition implements ParserDefinition { ... }

No XML registration is needed. The platform discovers @ExtensionImpl-annotated classes automatically at runtime.

Extension Default Properties

The following properties are available via the @ExtensionImpl annotation:

• id - set a unique ID via @ExtensionImpl(id = "myId")
• order - control ordering of extensions using @ExtensionImpl(order = "first"), @ExtensionImpl(order = "last"), or @ExtensionImpl(order = "before|after [id]")
• profiles - conditionally load the extension via @ExtensionImpl(profiles = ComponentProfiles.PRODUCTION). This allows restricting the extension to specific runtime profiles (e.g., production, testing).

If an extension instance needs to "opt out" in certain scenarios, it can throw ExtensionNotApplicableException in its constructor.

How to get the extension points list?

Extension Point List contains all available extension points in the Consulo Platform and from bundled plugins.

To find available extension points, browse the platform and plugin source code for interfaces and abstract classes annotated with @ExtensionAPI. Use Navigate | Symbol or your IDE's search functionality to locate them.