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Developer Materials

Bean Managed Transactions - Stepping Outside the Container (with JPA and JTA)

  • Author:
  • Contributors: Sande Gilda, Pete Muir , mmusgrov
  • Published: Nov 08, 2013
  • Level: Intermediate
  • Technologies:EJB, Bean Managed Transactions (BMT)
  • Target Product:EAP

What is it?

On occasion, the application developer requires finer grained control over the lifecycle of JTA transactions and JPA Entity Managers than the defaults provided by the Java EE container. This example shows how the developer can override these defaults and take control of aspects of the lifecycle of JPA and transactions.

This example demonstrates how to manually manage transaction demarcation while accessing JPA entities in Red Hat JBoss Enterprise Application Platform.

When you run this example, you will be provided with a Use bean managed Entity Managers checkbox. * If you check the checkbox, it shows the developer responsibilities when injecting an Entity Manager into a managed (stateless) bean. * If you uncheck the checkbox, shows the developer responsibilities when using JPA and transactions with an unmanaged component.

JBoss EAP ships with H2, an in-memory database written in Java. This example shows how to transactionally insert key value pairs into the H2 database and demonstrates the requirements on the developer with respect to the JPA Entity Manager.

Note: This quickstart uses the H2 database included with JBoss EAP 6. It is a lightweight, relational example datasource that is used for examples only. It is not robust or scalable and should NOT be used in a production environment!

NOTE: A Java EE container is designed with robustness in mind, so you should carefully analyse the scaleabiltiy, concurrency and performance needs of you application before taking advantage of these techniques in your own applications.

System requirements

The application this project produces is designed to be run on Red Hat JBoss Enterprise Application Platform 6.1 or later.

All you need to build this project is Java 6.0 (Java SDK 1.6) or later, Maven 3.0 or later.

Configure Maven

If you have not yet done so, you must Configure Maven before testing the quickstarts.

Start the JBoss Server

  1. Open a command line and navigate to the root of the JBoss server directory.
  2. The following shows the command line to start the server:

     For Linux:   JBOSS_HOME/bin/
     For Windows: JBOSS_HOME\bin\standalone.bat

Build and Deploy the Quickstart

NOTE: The following build command assumes you have configured your Maven user settings. If you have not, you must include Maven setting arguments on the command line. See Build and Deploy the Quickstarts for complete instructions and additional options.

  1. Make sure you have started the JBoss Server as described above.
  2. Open a command line and navigate to the root directory of this quickstart.
  3. Type this command to build and deploy the archive:

     mvn clean install jboss-as:deploy
  4. This will deploy target/jboss-bmt.war to the running instance of the server.

Access the application

The application will be running at the following URL: http://localhost:8080/jboss-bmt/.

You will be presented with a simple form for adding key/value pairs and a checkbox to indicate whether the updates should be executed using an unmanaged component. Effectively this will run the transaction and JPA updates in the servlet, not session beans. If the box is checked then the updates will be executed within a session bean method.

  1. To list all pairs leave the key input box empty.
  2. To add or update the value of a key fill in the key and value input boxes.
  3. Press the submit button to see the results.

Undeploy the Archive

  1. Make sure you have started the JBoss Server as described above.
  2. Open a command line and navigate to the root directory of this quickstart.
  3. When you are finished testing, type this command to undeploy the archive:

     mvn jboss-as:undeploy

Run the Quickstart in JBoss Developer Studio or Eclipse

You can also start the server and deploy the quickstarts from Eclipse using JBoss tools. For more information, see Use JBoss Developer Studio or Eclipse to Run the Quickstarts

Debug the Application

If you want to debug the source code or look at the Javadocs of any library in the project, run either of the following commands to pull them into your local repository. The IDE should then detect them.

    mvn dependency:sources
    mvn dependency:resolve -Dclassifier=javadoc

Recent Changelog

  • Nov 8, 2013(Sande Gilda):Bz1028448 Add spaces to end of metadata so it renders with a line break in HTML
  • Oct 11, 2013(Sande Gilda):Bz1017848 Missed warning for 3 quickstarts that us the H2 database. Update logging README.html
  • Oct 8, 2013(Sande Gilda):BZ1011833 Add HTML versions of README files and fix deployment instructions
  • Oct 2, 2013(Sande Gilda):README add Product Versions metadata remove versions in text remove temp repo from settings.xml
  • Sep 24, 2013(Sande Gilda):Remove references to web profile
  • Sep 24, 2013(Sande Gilda):Remove references to JBoss AS 7 from the quickstarts
  • Sep 23, 2013(Sande Gilda):Update metadata source URLs to new repository
  • Sep 13, 2013(Sande Gilda):JDF 487 Remove as from quickstart artifactId and archive names and access URLs in README files
  • Jun 12, 2013(Sande Gilda):Modify README file internal links to use generated anchors. Remove hard coded anchors. Fixed obsolete links and other markdown rendering problems
  • Feb 12, 2013(Sande Gilda):Add quickstart source repository of record to the README files
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