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Changes for Hibernate 3.5 applications

if your application uses Hibernate 3 classes that are not available in Hibernate 4, for example, some of the validator or search classes, you may see ClassNotFoundExceptions when you deploy your application. If you encounter this problem, you can try one of two approaches: You may be able to resolve the issue by copying the specific Hibernate 3 JARs containing those classes into the application "/lib" directory or by adding them to the classpath using some other method. In some cases this may result in ClassCastExceptions or other class loading issues due to the mixed use of the Hibernate versions, so you will need to use the second approach. You need to tell the server to use only the Hibernate 3 libraries and you will need to add exclusions for the Hibernate 4 libraries. Details on how to do this are described here: JPA Reference Guide.

In previous versions of the application server, the JCA data source configuration was defined in a file with a suffix of *-ds.xml. This file was then deployed in the server's deploy directory. The JDBC driver was copied to the server lib/ directory or packaged in the application's WEB-INF/lib/ directory. In AS7, this has all changed. You will no longer package the JDBC driver with the application or in the server/lib directory. The *-ds.xml file is now obsolete and the datasource configuration information is now defined in the standalone/configuration/standalone.xml or in the domain/configuration/domain.xml file. A JDBC 4-compliant driver can be installed as a deployment or as a core module. A driver that is JDBC 4-compliant contains a META-INF/services/java.sql.Driver file that specifies the driver class name. A driver that is not JDBC 4-compliant requires additional steps, as noted below.

DataSource Configuration

domain mode, the configuration file is the domain/configuration/domain.xml

standalone mode, you will configure the datasource in the standalone/configuration/standalone.xml

MySQL datasource element:

        <connection-url>jdbc:mysql://localhost:3306/YourApplicationURL</connection-url>        <driver-class> com.mysql.jdbc.Driver </driver-class>        <driver> mysql-connector-java-5.1.15.jar </driver>

       <security>            <user-name> USERID </user-name>            <password> PASSWORD</password>        </security>

example of the driver element for driver that is not JDBC 4-compliant. The driver-class must be specified since it there is no META-INF/services/java.sql.Driver file that specifies the driver class name.

 <driver-class>com.mysql.jdbc.Driver</driver-class>

JDBC driver can be installed into the container in one of two ways: either as a deployment or as a core module

Install the JDBC driver

Install the JDBC driver as a deployment

In AS7 standalone mode, you simply copy the JDBC 4-compliant JAR into the AS7_HOME/standalone/deployments directory

example of a MySQL JDBC driver installed as a deployment:     AS7_HOME/standalone/deployments/mysql-connector-java-5.1.15.jar

this annotation bypasses the management layer and as such it is recommended only for development and testing purposes

Defining a Managed DataSource

Installing a JDBC driver as a deployment

Installing the JDBC Driver

deployment or as a core module

managed by the application server (and thus take advantage of the management and connection pooling facilities it provides), you must perform two tasks.  First, you must make the JDBC driver available to the application server; then you can configure the data source itself.  Once you have performed these tasks you can use the data source via standard JNDI injection.

recommended way to install a JDBC driver into the application server is to simply deploy it as a regular JAR deployment.  The reason for this is that when you run your application server in domain mode, deployments are automatically propagated to all servers to which the deployment applies; thus distribution of the driver JAR is one less thing for administrators to worry about.

Note on MySQL driver and JDBC Type 4 compliance: while the MySQL driver (at least up to 5.1.18) is designed to be a Type 4 driver, its jdbcCompliant() method always return false. The reason is that the driver does not pass SQL 92 full compliance tests, says MySQL. Thus, you will need to install the MySQL JDBC driver as a module (see below).

Installing a JDBC driver as a module

<module xmlns="urn:jboss:module:1.0" name="com.mysql">  <resources>    <resource-root path="mysql-connector-java-5.1.15.jar"/>  </resources>  <dependencies>    <module name="javax.api"/>  </dependencies></module>

jboss-7.0.0.<release>/modules/com/mysql/main

define your module with a module.xml file, and the actual jar file that contains your database driver

content of the module.xml file

Under the root directory of the application server, is a directory called modules

module name, which in this example is com.mysql

where the implementation is, which is the resource-root tag with the path element

define any dependencies you might have.  In this case, as the case with all JDBC data sources, we would be dependent on the Java JDBC API's, which in this case in defined in another module called javax.api, which you can find under modules/javax/api/main as you would expect.

Defining the DataSource itself

   <datasource jndi-name="java:jboss/datasources/MySqlDS" pool-name="MySqlDS">      <connection-url>jdbc:mysql://localhost:3306/EJB3</connection-url>         <driver>com.mysql</driver>

    <drivers>      <driver name="com.mysql" module="com.mysql">        <xa-datasource-class>com.mysql.jdbc.jdbc2.optional.MysqlXADataSource</xa-datasource-class>      </driver>    </drivers>

jboss-7.0.0.<release>/domain/configuration/domain.xml or jboss-7.0.0.<release>/standalone/configuration/standalone.xml

Just bit of a warning when using this, there was a bug in 7.1.1 when you added mime type that prevented server to start.so please use 7.1.2 or 7.2 nightly builds where this is fixed.

javax.transaction package

Transactional

TxType

TxType

@Transactional

how the exceptions which reach a transactional interceptor affect the transaction in progress