Book Image

Apache MyFaces 1.2 Web Application Development

Book Image

Apache MyFaces 1.2 Web Application Development

Overview of this book

Hypes and trends (such as Web 2.0) cause a change in the requirements for user interfaces every now and then. While a lot of frameworks are capable of meeting those changing requirements, it often means you as a developer need in-depth knowledge of web standards, such as XHTML and JavaScript. A framework like Apache MyFaces that hides all details of how the page is rendered at the client and at the same time offers a rich set of tools and building blocks could save you a lot of time, not only when you're building a brand new application but also when you're adapting an existing application to meet new user interface requirements.This book will teach you everything you need to know to build appealing web interfaces with Apache MyFaces and maintain your code in a pragmatic way. It describes all the steps that are involved in building a user interface with Apache MyFaces. This includes building templates and composition components with Facelets, using all sorts of specialized components from the Tomahawk, Trinidad, and Tobago component sets and adding validation with MyFaces Extensions Validator.The book uses a step-by-step approach and contains a lot of tips based on experience of the MyFaces libraries in real-world projects. Throughout the book an example scenario is used to work towards a fully functional application when the book is finished.This step-by-step guide will help you to build a fully functional and powerful application.
Table of Contents (22 chapters)
Apache MyFaces 1.2
Credits
About the Author
Acknowledgement
About the Reviewers
Preface
Trinidad Tags
Trinidad Text Keys
Default JSF Error Messages
ExtVal Default Error Messages

Setting up Orchestra conversations


One of the really cool features of Orchestra is the possibility to create conversations. This feature can help us to solve a common problem in JSF applications—the lack of a scope that lasts exactly as long as we want it to. The request scope is only usable for very short-living data. Things that should last longer than a single request are usually put into the session scope. But the session scope stays in memory for as long as the user is logged in. That’s generally too long, which means that we have to manually remove objects that we don’t need anymore. Failing to remove those objects leads to too much memory usage and can also have undesired side effects.

Orchestra introduces the concept of conversations. A conversation is a page or a series of pages in which data can be manipulated by the user. The manipulated data will be persisted at the end of the conversation. During the conversation, we have a conversation scope that we can use to store temporary...