Defines JavaScript dependencies on a Component class. For adding multiple JavaScript files for a single component, you can use this annotation multiple times.

It is guaranteed that dependencies will be loaded only once. The files loaded will be in the same order as the annotations were on the class. However, loading order is only guaranteed on a class level; Annotations from different classes may appear in different order, grouped by the annotated class. Also, files identified by @JavaScript will be loaded after JsModule and before CssImport.

NOTE: Currently all frontend resources are bundled together into one big bundle. This means, that JavaScript files loaded by one class will be present on a view constructed by another class. For example, if there are two classes RootRoute annotated with @Route(""), and another class RouteA annotated with @Route("route-a") and @JavaScript("./src/javascript.js"), the javascript.js will be run on the root route as well.

External JavaScript dependencies (e.g. "http://example.com/some.js") are added in the same way as Page.addJavaScript(String) and the result is just adding a classic javscript element to the page. Other paths used in the value() method are considered as relative to frontend directory and they are added to the page as a JavaScript module (a javscript element with type="module"). In this case a JavaScript annotation behaves exactly as a JsModule annotation.

It's not possible to execute a function defined in JavaScript module via

 
 UI.getCurrent().getPage().executeJs("some_function_definied_in_module()");
 
 

Since:

1.0

Author:

Vaadin Ltd

See Also:

• Page.addJavaScript(String)
• JsModule