Document Information


Part I Introduction

1.  Overview

2.  Using the Tutorial Examples

Part II The Web Tier

3.  Getting Started with Web Applications

4.  JavaServer Faces Technology

5.  Introduction to Facelets

6.  Expression Language

7.  Using JavaServer Faces Technology in Web Pages

8.  Using Converters, Listeners, and Validators

9.  Developing with JavaServer Faces Technology

10.  JavaServer Faces Technology: Advanced Concepts

11.  Using Ajax with JavaServer Faces Technology

12.  Composite Components: Advanced Topics and Example

13.  Creating Custom UI Components and Other Custom Objects

Determining Whether You Need a Custom Component or Renderer

When to Use a Custom Component

When to Use a Custom Renderer

Component, Renderer, and Tag Combinations

Understanding the Image Map Example

Why Use JavaServer Faces Technology to Implement an Image Map?

Understanding the Rendered HTML

Understanding the Facelets Page

Configuring Model Data

Summary of the Image Map Application Classes

Steps for Creating a Custom Component

Creating Custom Component Classes

Specifying the Component Family

Performing Encoding

Performing Decoding

Enabling Component Properties to Accept Expressions

Saving and Restoring State

Delegating Rendering to a Renderer

Creating the Renderer Class

Identifying the Renderer Type

Implementing an Event Listener

Implementing Value-Change Listeners

Implementing Action Listeners

Defining the Custom Component Tag in a Tag Library Descriptor

Using a Custom Component

Creating and Using a Custom Converter

Creating a Custom Converter

Using a Custom Converter

Creating and Using a Custom Validator

Implementing the Validator Interface

Specifying a Custom Tag

Using a Custom Validator

Binding Component Values and Instances to Managed Bean Properties

Binding a Component Value to a Property

Binding a Component Value to an Implicit Object

Binding a Component Instance to a Bean Property

Binding Converters, Listeners, and Validators to Managed Bean Properties

14.  Configuring JavaServer Faces Applications

15.  Java Servlet Technology

16.  Uploading Files with Java Servlet Technology

17.  Internationalizing and Localizing Web Applications

Part III Web Services

18.  Introduction to Web Services

19.  Building Web Services with JAX-WS

20.  Building RESTful Web Services with JAX-RS

21.  JAX-RS: Advanced Topics and Example

Part IV Enterprise Beans

22.  Enterprise Beans

23.  Getting Started with Enterprise Beans

24.  Running the Enterprise Bean Examples

25.  A Message-Driven Bean Example

26.  Using the Embedded Enterprise Bean Container

27.  Using Asynchronous Method Invocation in Session Beans

Part V Contexts and Dependency Injection for the Java EE Platform

28.  Introduction to Contexts and Dependency Injection for the Java EE Platform

29.  Running the Basic Contexts and Dependency Injection Examples

30.  Contexts and Dependency Injection for the Java EE Platform: Advanced Topics

31.  Running the Advanced Contexts and Dependency Injection Examples

Part VI Persistence

32.  Introduction to the Java Persistence API

33.  Running the Persistence Examples

34.  The Java Persistence Query Language

35.  Using the Criteria API to Create Queries

36.  Creating and Using String-Based Criteria Queries

37.  Controlling Concurrent Access to Entity Data with Locking

38.  Using a Second-Level Cache with Java Persistence API Applications

Part VII Security

39.  Introduction to Security in the Java EE Platform

40.  Getting Started Securing Web Applications

41.  Getting Started Securing Enterprise Applications

42.  Java EE Security: Advanced Topics

Part VIII Java EE Supporting Technologies

43.  Introduction to Java EE Supporting Technologies

44.  Transactions

45.  Resources and Resource Adapters

46.  The Resource Adapter Example

47.  Java Message Service Concepts

48.  Java Message Service Examples

49.  Bean Validation: Advanced Topics

50.  Using Java EE Interceptors

Part IX Case Studies

51.  Duke's Bookstore Case Study Example

52.  Duke's Tutoring Case Study Example

53.  Duke's Forest Case Study Example



Handling Events for Custom Components

As explained in Implementing an Event Listener, events are automatically queued on standard components that fire events. A custom component, on the other hand, must manually queue events from its decode method if it fires events.

Performing Decoding explains how to queue an event on MapComponent using its decode method. This section explains how to write the class that represents the event of clicking on the map and how to write the method that processes this event.

As explained in Understanding the Facelets Page, the actionListener attribute of the bookstore:map tag points to the MapBookChangeListener class. The listener class's processAction method processes the event of clicking the image map. Here is the processAction method:

public void processAction(ActionEvent actionEvent)
        throws AbortProcessingException {

    AreaSelectedEvent event = (AreaSelectedEvent) actionEvent;
    String current = event.getMapComponent().getCurrent();
    FacesContext context = FacesContext.getCurrentInstance();
    String bookId = books.get(current);
    context.getExternalContext().getSessionMap().put("bookId", bookId);

When the JavaServer Faces implementation calls this method, it passes in an ActionEvent object that represents the event generated by clicking on the image map. Next, it casts it to an AreaSelectedEvent object (see tut-install/examples/case-studies/dukes-bookstore/src/java/dukesbookstore/listeners/ Then this method gets the MapComponent associated with the event. It then gets the value of the MapComponent object's current attribute, which indicates the currently selected area. The method then uses the value of the current attribute to get the book's ID value from a HashMap object, which is constructed elsewhere in the MapBookChangeListener class. Finally the method places the ID obtained from the HashMap object into the session map for the application.

In addition to the method that processes the event, you need the event class itself. This class is very simple to write: You have it extend ActionEvent and provide a constructor that takes the component on which the event is queued and a method that returns the component.

Here is the AreaSelectedEvent class used with the image map:

public class AreaSelectedEvent extends ActionEvent {
    public AreaSelectedEvent(MapComponent map) {
    public MapComponent getMapComponent() {
        return ((MapComponent) getComponent());

As explained in the section Creating Custom Component Classes, in order for MapComponent to fire events in the first place, it must implement ActionSource. Because MapComponent extends UICommand, it also implements ActionSource.