Custom Facelet component in JSF

Question

Is it possible to create a custom JSF core Facelet component. Something like of , or

Answer 1

It are in essence taghandlers. I.e. classes extending from TagHandler.

Here's a Hello World taghandler.

com.example.HelloTagHandler

public class HelloTagHandler extends TagHandler {

    public HelloTagHandler(TagConfig config) {
        super(config);
    }

    @Override
    public void apply(FaceletContext context, UIComponent parent) throws IOException {
        // Do your job here. This example dynamically adds another component to the parent.
        if (ComponentHandler.isNew(parent)) {
            UIOutput child = new HtmlOutputText();
            child.setValue("Hello World");
            parent.getChildren().add(child);
        }

        nextHandler.apply(context, parent); // Delegate job further to first next tag in tree hierarchy.
    }

}

/WEB-INF/my.taglib.xml

    http://example.com/my
    
        hello
        com.example.HelloTagHandler
    

/WEB-INF/web.xml (note: this part is not mandatory when my.taglib.xml is in /META-INF folder of a JAR file inside /WEB-INF/lib like as with JSF component libraries):

    javax.faces.FACELETS_LIBRARIES
    /WEB-INF/my.taglib.xml

Usage in /some.xhtml

...

To see the source code of Mojarra implementation of and , click the links.

See also:

• When to use , tag files, composite components and/or custom components?