Ujorm
Ujorm是一个开源的对象-关系映射实现框架(ORM )。拥有一个类型安全的查询语言,可以让java编译器检查语法错误。支持懒加载,拥有比Hibernate更高的性能。ORM模型既可以通过Java源代码配置,也通过注释或XML文件配置。ORM可映射数据库中的表格,视图或自定义的SQL查询。JDBC查询参数通过问号传递给 PreparedStatement,以提高安全性。所有内部对象缓存都基于WeakHashMap类实现,所以在处理大量事务的时候不会引会内存溢出错误。
Why a new ORM mapping?
- framework has a type safe query language which allows the java compiler find a syntax error similar like a 4GL language
- never more a LazyInitialization exception though a lazy initialization is supported
- no confusing proxy business objects
- no list properties are supported but a special object called UjoIterator is designed for a collection. The UjoIterator provides a toList() method for example
- easy to configure the ORM model by java source code, optionally by annotations and a XML file
- great performance, e.g. multi SELECT is eight times faster in comparison with Hibernate
- small size of JAR file and no more library dependencies
Some other features
- resources for ORM mapping can be a database table, view, or your own SQL SELECT
- JDBC query parameters are passed by a question notation to the PreparedStatement for a high security
- all persistent objects are based on the OrmUjo interface, namely on the OrmTable implementation
- internal object cache is based on the WeakHashMap class so that large transactions does not cause any OutOfMemoryException
- the API was inspired mainly by Canyenne and Hibernate frameworks. I would like to thank the authors for good work.