How to Use BTM as the Transaction Manager in Tomcat 6.x

Original http://docs.codehaus.org/display/BTM/Tomcat13

These instructions have been verified against BTM 1.3.1.

Contents

• Step 1: copy the BTM jars
• Step 2: Configure BTM as the Transaction Manager
• Step 3: Configure datasources that are transaction aware
• Step 4: Configure Transaction Manager and datasources initialization in your META-INF/context. xml
• Step 5: Configure datasources references in your web. xml

Step 1: copy the BTM jars

Copy the following jars from the BTM distribution to the TomcatLIB/Directory:

• Btm-1.3.1.jar
• Geronimo-jta_1.0.1B_spec-1.0.1.jar
• Slf4j-api-1.5.2.jar
• Slf4j-jdk14-1.5.2.jar
• Btm-tomcat55-lifecycle.jar (It works with both Tomcat 5.5 and tomcat 6)

You will also need to copy your JDBC driver's JAR file in that same folder. In this example, we 've used Derby 10.3.2.1 so we copiedDerby. JarIn Tomcat'sLIB/Directory.

Step 2: Configure BTM as the Transaction Manager

Windows: create a file namedSetenv. batWith the following commands under Tomcat'sBin/Directory:

Set catalina_opts =-dbtm. Root = % catalina_home %-dbitronix. tm. Configuration = % catalina_home % \ conf \ btm-config.properties

UNIX: create a file namedSetenv. ShWith the following commands under Tomcat'sBin/Directory:

Catalina_opts =& Quot;-dbtm. Root = $ catalina_home-dbitronix. tm. Configuration = $ catalina_home/CONF/btm-config.properties & quot"

Now create a file namedBtm-config.propertiesWith the following properties under Tomcat'sConf/Directory:

Bitronix. tm. serverid = tomcat-btm-node0Bitronix. tm. Journal. disk. logpart1filename =$ {BTM. Root}/work/btm1.tlogBitronix. tm. Journal. disk. logpart2filename =$ {BTM. Root}/work/btm2.tlogBitronix. tm. Resource. Configuration =$ {BTM. Root}/CONF/resources. Properties

Then edit the file namedServer. xmlUnder Tomcat'sConf/Directory. Under this line:

<Listener classname ="Org. Apache. Catalina. mbeans. globalresourceslifecyclelistener" />

Add this one:

<Listener classname ="Bitronix. tm. Integration. tomcat55.btmlifecyclelistener" />

The<Listener>Tag will make sure BTM is started when Tomcat starts up and shutdown when Tomcat shuts down.

The next step is to edit the file namedContext. xmlUnder Tomcat'sConf/Directory. Under this line:

<Watchedresource> WEB-INF/Web. xml </watchedresource>

Add this one:

<Transaction factory ="Bitronix. tm. bitronixusertransactionobjectfactory" />

The<Transaction>Tag will bind the Transaction Manager at the standard JNDI locationJava: COMP/usertransaction.

Finally, create an empty file namedResources. PropertiesUnder Tomcat'sConf/Directory.

Step 3: Configure datasources that are transaction aware

You have to put your CES configurations in Tomcat'sConf/resources. PropertiesFile. Here's an example of using BTM with a datasource that implements javax. SQL. xadatasource:

Resource. ds1.classname = org. Apache. Derby. JDBC. embeddedxadatasourceResource. ds1.uniquename = JDBC/mydatasourceResource. ds1.minpoolsize =0Resource. ds1.maxpoolsize =5Resource. ds1.driverproperties. databasename = ../work/db1Resource. ds1.driverproperties. createdatabase = create

This will createBitronix. tm. Resource. JDBC. poolingdatasourceThat implementsJavax. SQL. datasourceAnd interacts withJavax. SQL. xadatasourceProvided in this instance by derby.

if your database vendor does not provide an xadatasource , you can use BTM's bitronix. TM. resource. JDBC. LRC. lrcxadatasource as the xadatasource to allow your database connections to be controlled by the Transaction Manager:

Resource. ds2.classname = bitronix. tm. Resource. JDBC. LRC. lrcxadatasourceResource. ds2.uniquename = JDBC/examplenonxadsResource. ds2.minpoolsize =0Resource. ds2.maxpoolsize =5Resource. ds2.driverproperties. driverclassname = org. Apache. Derby. JDBC. embeddeddriverResource. ds2.driverproperties. url = JDBC: Derby: ../work/DB2; Create =True

Again, we 've used Derby as an example, but asLrcxadatasourceUses only the class name and URL ofJava. SQL. Driver, You can use it with any database providing a JDBC driver.

Step 4: Configure Transaction Manager and datasources initialization in your META-INF/context. xml

In the web application where you want one or more datasource to be used, you have to create a META-INF/context. xml file.

< Context > < Resource Name = "JDBC/mydatasource" Auth = "Container" Type = "Javax. SQL. datasource" Factory = "Bitronix. tm. Resource. resourceobjectfactory" Uniquename = "JDBC/mydatasource" /> < Resource Name = "JDBC/examplenonxads" Auth = "Container" Type = "Javax. SQL. datasource" Factory = "Bitronix. tm. Resource. resourceobjectfactory" Uniquename = "JDBC/examplenonxads" /> </ Context >

The<Resource>Tags will bind a bitronix. tm. Resource. resourceobjectfactory object each, passing it a javax. Naming. Reference containing a javax. Naming. stringrefaddr containing the datasource'sUniquenameAsAddrtype.

Tomcat specific This mechanism is internal to Tomcat. You do not have to worry about how it works,Bitronix. tm. Resource. resourceobjectfactoryClass will handle those details.

TheBitronix. tm. Resource. resourceobjectfactoryClass will return the datasource previusly configured in Tomcat'sConf/resources. PropertiesWith the specifiedUniquenameWhen it is fetched from JNDI.

Step 5: Configure datasources references in your web. xml

Before your code can access configured datasources via jndi enc URLs, You need to declare resource references in yourWeb. xml:

<? XML Version = "1.0" Encoding = ISO-8859-1" ?>   <! Doctype web-app public "-// Sun Microsystems, Inc. // DTD web application 2.3 // en" Http://java.sun.com/dtd/web-app_2_3.dtd> < Web-app > < Resource-env-ref > < Resource-env-ref-name > JDBC/mydatasource </ Resource-env-ref-name > < Resource-env-ref-type > Javax. SQL. datasource </ Resource-env-ref-type > </ Resource-env-ref > < Resource-env-ref > < Resource-env-ref-name > JDBC/examplenonxads </ Resource-env-ref-name > < Resource-env-ref-type > Javax. SQL. datasource </ Resource-env-ref-type > </ Resource-env-ref > </ Web-app >

Now you can do JNDI lookups on those URLs to access the configured datasources:

Datasource examplenonxads = (datasource) CTX. Lookup ("Java: COMP/ENV/jdbc/examplenonxads");Datasource mydatasource = (datasource) CTX. Lookup ("Java: COMP/ENV/jdbc/mydatasource");

And you can do JNDI lookups on this URL to access the Transaction Manager:

Usertransaction ut = (usertransaction) CTX. Lookup ("Java: COMP/usertransaction");