The bmt
quickstart demonstrates Bean-Managed Transactions (BMT), showing how to manually manage transaction demarcation while accessing JPA entities.
The bmt
quickstart demonstrates how to manually manage transaction demarcation while accessing JPA entities in WildFly Application Server.
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.
When you run this example, you are presented with a Use bean managed Entity Managers checkbox.
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If you check the checkbox, it shows the developer responsibilities when injecting an Entity Manager into a managed (stateless) bean.
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If you uncheck the checkbox, shows the developer responsibilities when using JPA and transactions with an unmanaged component.
WildFly 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.
The application this project produces is designed to be run on WildFly Application Server 12 or later.
All you need to build this project is Java 8.0 (Java SDK 1.8) or later and Maven 3.3.1 or later. See Configure Maven to Build and Deploy the Quickstarts to make sure you are configured correctly for testing the quickstarts.
In the following instructions, replace WILDFLY_HOME
with the actual path to your WildFly installation. The installation path is described in detail here: Use of WILDFLY_HOME and JBOSS_HOME Variables.
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Open a terminal and navigate to the root of the WildFly directory.
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Start the WildFly server with the default standalone profile by typing the following command.
$ WILDFLY_HOME/bin/standalone.sh
NoteFor Windows, use the WILDFLY_HOME\bin\standalone.bat
script.
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Make sure you have started the WildFly server as described above.
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Open a terminal and navigate to the root directory of this quickstart.
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Type this command to build and deploy the archive:
$ mvn clean install wildfly:deploy
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This will deploy
target/{artifactId}.war
to the running instance of the server.
The application will be running at the following URL: http://localhost:8080/{artifactId}/.
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.
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To list all pairs leave the key input box empty.
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To add or update the value of a key fill in the key and value input boxes.
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Click the submit button to see the results.
You will see the following warnings in the server log. You can ignore these warnings.
WFLYJCA0091: -ds.xml file deployments are deprecated. Support may be removed in a future version. HHH000431: Unable to determine H2 database version, certain features may not work
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Make sure you have started the WildFly server as described above.
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Open a terminal and navigate to the root directory of this quickstart.
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When you are finished testing, type this command to undeploy the archive:
$ mvn wildfly:undeploy
You can also start the server and deploy the quickstarts or run the Arquillian tests from Eclipse using JBoss tools. For general information about how to import a quickstart, add a WildFly server, and build and deploy a quickstart, see Use JBoss Developer Studio or Eclipse to Run the Quickstarts.