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JBoss Seam
 
an application prone to errors. JEE developers refer this problem as the “XML hell”. This way of using the XML files is popular among the whole Java community as “the XML abuse”. Java community made the successful attempts to replace these XML files with the introduction of the annotations to the Java source code.

To promote the use of annotations at enterprise level officials of the Java standardization body introduced EJB3. EJB3 provides the options to use the annotations in place of the XML file and expands the sphere of annotation-based programming model for the web application.

It doesn’t mean that XML is fully useless, XML best suits for specification of web application page flows and can also define the work flow of the business process. XML files enable a user to centrally manage the work flow of the entire web application rather than to scatter the information around the Java source file.

7. Designed for Easy integration Testing

Seam is mainly designed to simplify the testing process. Unit testing is easier with seam as all the Seam components are nothing but the annotated POJO. Simply one need to create the POJO instances which can be tested with different testing frameworks such as TestNG and JUnit. If there requires any interaction between the Seam components then just create the individual instances of those components and manually establish the relationship between them.

Testing of the entire Seam application is a little bit complex because it needs entire application to run inside the Seam container. Seam comes along with an embedded lightweight container to handle the integrated testing. One can also programmatically load the Seam container to run the test into the test framework.

8. Designed for Stateful Web Applications

Seam also designs stateful web applications which are inherently multi-user. Today, most of the business applications are stateful and transactional. In case of
  Seam, all the components of an application are stateful therefore it is quite easy to use seam for managing states as compared to HTTP session. Seam applications does not require a developer to write the state management code, but simply it, itself annotates the scope of the components, lifecycle methods and other stateful properties required. Stateful components of Seam also manages the user states in a better way in comparison to conventional HTTP sessions.

Seam automatically ties up the transactions and the database caches with the application state. It temporarily holds database updates in memory and commits updates to the database while ending the conversation. For complex stateful applications, in-memory cache reduces the database load of the application.

Seam takes state management in web applications a big step further by supporting integration with the Open Source JBoss jBPM business process engine. One can now specify the work flows of different people in the organization (i.e., customers, managers, technical support etc.) and use the work flow to drive the application, instead of relying on the UI event handlers and databases.

9. Great Tools Support

Seam simplifies to accomplish difficult tasks with JSF. Generally, to bookmark a JSF web page and get it via HTTP GET is hard. Generating a bookmarkable resultful web page with Seam is quite simple. Seam makes the JSF applications efficient by providing a number of JSF tags and use of annotations increases the “web friendliness”.

Simultaneously, Seam expands the web tier to the business components and also expands the EJB3 component model to POJOs. Even though Seam also integrates a number of commonly used other open source framework like JBoss Portal, jBPM, JBossMicrocontainer, JBoss Rules etc.

Although Seam is integrated with Java EE 5.0, it doesn’t mean that it is limited to Java EE 5.0 servers. Seam applications can also be deployed
Oct 2007 | Java Jazz Up |29
 
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