Book Image

Enterprise Application Development with Ext JS and Spring

By : Gerald Gierer
Book Image

Enterprise Application Development with Ext JS and Spring

By: Gerald Gierer

Overview of this book

Spring and Ext JS are cutting edge frameworks that allow us to build high performance web applications for modern devices, that are now consuming data at a faster rate than ever before. It is the appropriate time for you to understand how to best leverage these technologies when architecting, designing, and developing large scale web development projects. This practical guide condenses an approach to web development that was gained from real world projects, and outlines a simple, practical approach to developing high performance, and enterprise grade web applications. Starting with configuring Java, NetBeans, and MySQL to prepare your development environment, you will then learn how to connect your NetBeans IDE to the MySQL database server. We will then explore the Task Time Tracker (3T) project database structure and populate these tables with test data. Following on from this, we will examine core JPA concepts after reverse engineering the domain layer with NetBeans. Leveraging the Data Access Object design pattern, you will learn how to build the Java DAO implementation layer assisted by generics in base classes, followed by a Data Transfer Object enabled service layer to encapsulate the business logic of your 3T application. The final chapters that focus on Java explore how to implement the request handling layer using Spring annotated controllers, and deploy the 3T application to the GlassFish server. We will then configure the Ext JS 4 development environment and introduce key Ext JS 4 concepts, including MVC and practical design conventions. Covering a variety of important Ext JS 4 strategies and concepts, you will be fully-equipped to implement a variety of different user interfaces using the Ext JS MVC design pattern. Your journey ends by exploring the production build and deployment process using Maven, Sencha Cmd and GlassFish.
Table of Contents (22 chapters)
Enterprise Application Development with Ext JS and Spring
About the Author
About the Reviewers
Introducing Spring Data JPA

Building the service layer

The service layer classes and interfaces will follow the same naming conventions of our DAO layer, where Service simply replaces the Dao equivalent name:

Our first definition will be for the Result class.

The Result Data Transfer Object

The service layer will communicate with the request handling tier through interfaces that return Result Data Transfer Objects (DTO). The DTO design pattern is commonly used in enterprise application programming to transfer data between different layers or subsystems. Our Result DTO will have the following three properties:

  • boolean success: This property is used if the action was successful and an appropriate data payload is available

  • String msg: This is a message that may be used by the client for logging or informational purposes

  • <T> data: This is a generically typed data payload that will be consumed by the request handling layer

The Result class is also a Value Object (VO), an immutable object whose state cannot be changed after...