JPOX provides transparent persistence of Java objects. It fully complies with the JDO1.0/JDO2.0/JDO2.1 specifications, as well as implementing the JPA1 specification. It supports persistence to all of the major RDBMS on the market today, as well as DB4O. It allows querying using either JDOQL, SQL, or JPQL. It comes with its own byte-code enhancer. Its 1.1 release is Sun's "Reference Implementation" (RI) for JDO2.0, and its 1.2 release is the RI for JDO2.1. It is highly extensible using OSGi technology.
License: The Apache License 2.0
Changes:
Support for JDOQL and JPQL subqueries has been added along with support for JPQL IN, ESCAPE, TRIM, CURRENT_DATE, CURRENT_TIME, and CURRENT_TIMESTAMP. JPOX extensions have been added to allow more control over generated SQL for problematic JDOQL queries. Several bugs have been fixed. Full compliance with JDO2.1 has been achieved.
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