Hibernate Framework: The favorite ORM tool

Hibernate is a powerful object relational mapping tool written in Java. Hibernate allows you to develop persistent classes mirroring object oriented paradigm - including association, inheritance, polymorphism, composition, and collections. Hibernate has its own portable SQL based langugage (HQL) or can work with native SQL. Hibernate simplifies persistence programming tasks by providing a higher abstraction.

Hibernate is a suite of tools for ORM, including Hibernate core, Hibernate Tools, Hibernate search etc. Only core is required for basic ORM. Each component is available as a separate download.
Hibernate stores table to class mapping in an external XML file. Following is a sample,
<hibernate-mapping>
    <class name=”tasks.Task” table=”TASKS”>
        <id name=”id” column=”TASK_ID”>
            <generator class=”native”/>
        </id>
        <property name=”date” type=”timestamp” column=”TASK_DATE”/>
        <property name=”title”/>
    </class>
</hibernate-mapping>