WAS v8.5 > Administer applications and their environment > Welcome to administering EJB applications > Administer applications that use the Java Persistence API

Configure JPA to work in the environment

You have developed the applications to work with JPA and now configure your JPA applications to work in the environment.

Specify options for the database as a part of configuring JPA applications. The application server manages access to data sources. We can configure the data sources, connection pooling, and Java Transaction API (JTA) service in the dmgr console. If we have a specific data source for the application, configure the data source before you install your JPA application.

1. Configure your data sources through the dmgr console. See the topic, Configure a JDBC provider and data source.

2. Specify the JNDI names for the <jta-data-source> and <non-jta-data-source> elements. For example to use JNDI lookup:
   <jta-data-source>jdbc/myJTADataSource</jta-data-source> <non-jta-data-source>jdbc/myNonJTADataSource</non-jta-data-source>

   If we use the component name space method (for example, java:comp/env) for data source retrieval, ensure the application defines these resource references so that we can use these JNDI names to access the data source. This component name space configuration provides more flexibility if you must alter the configuration for the data source. Otherwise, the standard, direct JNDI is used as the data source name. For more information about using the JNDI interface, see the topic, Developing applications that use JNDI. For example, the persistence.xml file would have an entry like the following:

   <jta-data-source>java:comp/env/jdbc/DataSourceJNDI</jta-data-source>
   OR
   <jta-data-source>jdbc/DataSourceJNDI</jta-data-source>
3. Configure persistence provider support in the application server.
   1. Configure the JPA default persistence provider.

   2. Optional: Use third-party persistence providers.

For more information about the commands, classes or other OpenJPA information, refer to the Apache OpenJPA User Guide.

Subtopics

• Configure a JDBC provider and data source
  For access to relational databases, applications use the JDBC drivers and data sources that you configure for the application server.
• Configure the default JTA and non-JTA data source JNDI names
  The Java Transaction API (JTA) and non-JTA data sources to be used for an application can be specified through the <jta-data-source> and <non-jta-data-source> elements of the persistence.xml file within an EJB module.
• Associate persistence providers and data sources
  Java Persistence API (JPA) applications specify the underlying data source used by the persistence provider to access the database.
• Configure persistence provider support in the application server
  Persistence providers are implementations of the JPA specification and can be deployed in the Java EE compliant application server that supports JPA persistence.
• Configure the WSJPA FastPath for improved performance
  The Java Persistence API (JPA) is a very flexible specification that provides guidelines on how implementors are to translate relational data to Java object form. Due to the flexible nature of this API, a large amount of work is completed at runtime by the API provider to determine how to correctly load relational data into object form. This flexibility results in a runtime that, under certain circumstances, has to continually run redundant code to ensure that data is loaded properly. By giving up some of this flexibility, the WSJPA FastPath optimization attempts to skip much of this redundant code and generates highly optimized code that interacts directly with the JDBC layer.
• Tasks: IBM Optim pureQuery Runtime
  IBM Optim pureQuery Runtime provides JPA with an alternative way to access a database. PureQuery supports static Structured Query Language (SQL).

Related

Map persistent properties to XML columns for JPA
Associate persistence providers and data sources
Configure a JDBC provider and data source
Tasks: IBM Optim pureQuery Runtime
Configure pureQuery to use multiple DB2 package collections
Configure JDBC providers to use pureQuery to access DB2
Configure JDBC providers to use pureQuery to access Informix
Configure data source JDBC providers to use pureQuery in a Java SE environment
Develop applications that use JNDI

Reference:

Criteria API

Related information:

Apache OpenJPA User Guide: JPA

Apache OpenJPA User Guide: JPA Criteria

Apache OpenJPA User Guide

Dynamic, typesafe queries in JPA 2.0
IBM System i: PTF Cover Letters
IBM Support: Fix Central for DB2 UDB for iSeries V6R1
IBM Support: Fix Central for DB2 UDB for iSeries V5rR3

+

Search Tips   |   Advanced Search