Analysis of Java EE Web application Architecture (II.)

Advantages and Disadvantages

Advantages:

Some developers have started to adopt and promote this framework

As an open source project, there are many advanced implementation ideas

Good support for large-scale applications

There is a centralized page navigation definition

Disadvantages:

Not the industry standard

Lack of support for development tools

Complex Taglib, which takes a long time to master

HTML form and Actionform are more closed, but this is the essence of it.

Modifications suggest that the Actionform property's settings and accessors be modified to read or generate XML documents, and then the HTML form and the Actionform are exchanged with XML documents to make them loosely coupled, adapting to the easily changing data structure of the application.

2.2. JATO

The Jato application framework is the old name of the iplanet application framework. It is a mature and powerful application framework for developing Web applications based on the Java EE standard. Combines concepts such as display fields, application events, component hierarchies, and page-centric development methodologies, as well as MVC and service-to-worker service-to-workers design patterns. The Jato is suitable for medium, large and ultra-large scale Web applications. But it is not an enterprise Layer application framework, that is, it does not directly provide the method of creating enterprise layer components such as EJB, WEB services, but it can construct the customer application to access the enterprise layer components.

This framework features three main components:

iplanet application Framework Core;

iplanet application framework components;

iplanet application Framework extension.

The application framework core defines the basic interface, the object protocol, the simple component, and the minimum core of the Iplanet application framework program. Includes view simple components, model simple components, request distribution components, and reusable command objects. The Iplanet Application framework component provides developers with a high-level reuse component that leverages the basic interfaces, protocols, and components defined by the framework core, which have horizontal components that are not related to a particular visual effect, while also having a vertical component that is intentionally provided to accommodate a specific practical environment and improve usability. Framework extension implements a framework-compatible approach to accessing non-EE environments. Typically, extensions are used by framework applications to seamlessly access the Java EE container-specific features. The Jato platform stack diagram clearly expresses the situation.

Jato's greatest power: for fast-developing users, you can increase productivity with framework components and extensions, and for users who require greater flexibility, you can implement the interface provided by the framework core to maintain the framework compatibility of your application.

This diagram represents the implementation of a JATO application that can be implemented simply by controlling the component Module1servlet, the View component Listcustomersviewbean and the model component Customersmoduleimpl, and a listcustomers.jsp file for the Client Agent display interface. And clearly indicate the inheritance relationship between these components and the JATO framework components.

The Jato Tag library provides an interface between a View object and a JSP file. The tag handler in the library is responsible for synchronizing and exchanging information between the View object and the JSP-generated client document. This diagram clearly expresses this correspondence.

The front-end control component receives any request from the user, which can be specified in Web. XML with the request distribution component responsible for view management and navigation, and the front-end control component encapsulated in Applicationservletbase. Application developers need to implement one such inheritance for each subsystem (human resources, finance, CRM, etc.).

The request distribution component distributes the request to the worker, and the worker implements the command interface. This interface can be implemented by the application developer. Jato provides a default implementation: Defaultrequesthandingcommand, which passes the request to a specific event of the view component.

A combined view is a hierarchical relationship when the view component is displayed to the user: The root view is an object of the Viewbean class, and the container view is an object of the class Displayfield. Containerview class. The hierarchical relationships of the view component classes are as follows:

Analysis of Java EE Web application Architecture (II.)