Very interesting approach!
"Apache Empire-db is an Open Source relational data persistence component which allows database vendor independent dynamic query definition as well as safe and simple data retrieval and updating. Compared to most other solutions like e.g. Hibernate, TopLink, iBATIS or JPA implementations, Empire-db takes a considerably different approach, with a special focus on compile-time safety, reduced redundancies and improved developer productivity."
Spring, JPA, and JTA with Hibernate and JOTM
2007-04-24 20:35
have been struggling for a couple of hours today to modify a Spring JPA configuration with a single datasource, Hibernate as the JPA provider and the JpaTransactionManager to a configuration with two XA datasources, Hibernate as the JPA provider, and the JtaTransactionManager with JOTM as the standalone JTA provider.
since the Spring and Hibernate reference manual and Javadoc documentation merely contain a number of hints on how to configure JPA with a JTA transaction manager and others are struggling as well i decided to post how i finally got it to work.
With the addition of generics in Java 5, writing a custom DAO for each domain object is no longer required. There are a wide variety of articles on creating generic DAOs, but my current project uses the approach from this IBM DeveloperWorks article. This approach was choses mainly because of the clearly written article and the integration with Spring. You should be able to extend any generic DAO based on Spring to implement the stored procedure configuration.
About
AutoDAO is a Generic DAO on steroids implementation for Java.
This project was inspired by Don't repeat the DAO! article by Per Mellqvist.
Main features
* Ready to use CRUD operations
* Zero persistence code for common DAO queries
* Annotation-driven auto-configuration
* Spring Framework custom namespace for easy to use configuration
* Hibernate/JPA support
What does it do?
Given an accessible database schema, the Hibernate POJO Generator produces all the Java code necessary to access each field in each table via the Hibernate persistence framework. Additionally, the generator also creates all the necessary helper classes and test units for each component.
The Envers project aims to enable easy versioning of persistent JPA classes. All that you have to do is annotate your persistent class or some of its properties, that you want to version, with @Versioned. For each versioned entity, a table will be created, which will hold the history of changes made to the entity. You can then retrieve and query historical data without much effort.
Similarly to Subversion, the library has a concept of revisions. Basically, one transaction commit is one revision (unless the transaction didn't modify any versioned entities). As the revisions are global, having a revision number, you can query for various entities at that revision, retrieving a (partial) view of the database at that revision.
The goal of Autofetch is reduce the modularity penalty and programmer burden of specifying associations which should be loaded with an object query. These specifications are sometimes are called fetch profiles, prefetch directives, or joins. These specifications are an important performance optimization because they reduce the number of round-trips to a persistence store whether that be a relational database, object database, or flat file. Autofetch is a library which integrates with object persistence tools and automatically handles prefetching data. Using dynamic program profiling, Autofetch determines the right prefetch directives for each query a program executes.
This article presents with an solution on how to page through large amountsofdata effectively without taking down your database and without keeping it all in memory.
Hibernate is a powerful, high performance object/relational persistence and query service. Hibernate lets you develop persistent classes following object-oriented idiom - including association, inheritance, polymorphism, composition, and collections. Hibernate allows you to express queries in its own portable SQL extension (HQL), as well as in native SQL, or with an object-oriented Criteria and Example API.