JMS pools configuration
BTM XA connection factories can be created - like their JDBC counterparts - via some java code or via a BTM-specific tool called the Resource Loader. You are free to choose the method you prefer, there is absolutely no difference between them.
BTM comes bundled with a JMS XA connection pool. It is very easy to configure it. You basically have to create an instance of bitronix.tm.resource.jms.PoolingConnectionFactory set some properties and you're done.
Here is an example of datasource creation that connects to an ActiveMQ JMS server:
1. The Bitronix
PoolingConnectionFactory is a javabean that implements
2. You have to specify the JMS server's
XAConnectionFactory implementation here. It might be that this class cannot be directly instantiated because the JMS specification only specifies that implementations of this class should be available from JNDI. If your vendor only allows
XAConnectionFactory implementations to be acquired from JNDI, you should have a look at XA Connection factories only available from JNDI.
3. Each connection factory must be assigned a unique name. This is required for distributed crash recovery.
4. This connection factory will pool 5 connections.
5. You have to set
allowLocalTransactions to true if you want to be able to send or receive messages outside of XA transactions scope.
6. The driverProperties is a
java.util.Properties object. You have to add into it a set of property name / property value of the
ActiveMQXAConnectionFactory class. You have to refer to the JMS server's documentation to know what can / has to be set. The ActiveMQXAConnectionFactory javadoc contains this list for the ActiveMQ case. BTM will perform conversion from
boolean or to
int when necessary.
7,8. You can now use the
PoolingConnectionFactory like any other
9. Remember to close the
PoolingConnectionFactory after you're done with it to release the connections.
Like for JDBC, the connection pool will be initialized during the first call to
createConnection(). It might be desirable to initialize the pool eagerly, like during application startup rather than having to wait for the first request. This can be done by calling
Now line 7 will initialize the pool and create the 5 connections to the database instead of line 8.
Using the Resource Loader
A connection factory configuration utility is also bundled with BTM. It is convenient to use it rather than create your connection factory in code. Refer to the Resource Loader page for more details.
Here is the equivalent Resource Loader configuration of the previous code example:
You just have to write those properties in a simple text file and tell BTM where to load it by setting the
resourceConfigurationFilename property of the Configuration object.
Now you also have to know how to get the connection factory created by the Resource Loader. There are multiple ways:
bitronix.tm.resource.bind=trueto your resource loader properties file. The connection factories will then be bound to the default JNDI server using their
uniqueNameas their JNDI name.
- Another way (in case the JNDI context is read only, like in Tomcat) is to bind a
bitronix.tm.resource.ResourceFactoryobject, passing it a
javax.naming.StringRefAddrcontaining the connection factory's
addrTypesomewhere in your JNDI tree. The
bitronix.tm.resource.ResourceFactoryclass will just return the connection factory with the specified
uniqueName. This is explained more in-depth in the Jetty and Tomcat documentation pages.
- The last way is to call
bitronix.tm.resource.ResourceRegistrar.get(String uniqueName). This is the least preferred method as this ties your code to BTM which you probably want to avoid.