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JPA Reference (JavaDoc)

This reference contains the API documentation (similar to JavaDoc) of the Java Persistence API (JPA) 2.0. The content is derived from the original JPA documentation (in the EclipseLink JPA 2 RI ... into the following sections: The purpose of these documentation pages is to serve as a reference. In

JDO Reference (JavaDoc)

This reference contains the API documentation (similar to JavaDoc) of JDO 2.2. The content is derived from the original JDO documentation with some additions and notes. The most basic JDO types are: All the other JDO types are organized into the following sections:

Entity Management Settings

for entities: The ref attribute specifies the reference type for holding non dirty entities in ... ", "soft" and "strong". Modified entities are always held by strong references in the persistence

Database Explorer

navigation. Because every reference between two database objects is represented by a parent-child ... to construct and store the new entity objects. Editing Values and References You can edit simple field ... the new value. Use the Edit > Edit Multi Line String command to edit a multi line string. Reference

Retrieving JPA Entity Objects

accessed. The getReference method is useful when a reference to an entity object is required but not its content, such as when a reference to it has to be set from another entity object. Retrieval by Eager ... unacceptable. A persistent reference field can be excluded from this automatic cascaded retrieval by

Storing JPA Entity Objects

an Employee instance with a reference to an Address instance: Employee employee = new Employee ... instance. To avoid a dangling reference in the database, an IllegalStateException is thrown on commit if a persisted entity object has to be stored in the database in a transaction and it references

Soft Reference Object Cache Recommendation

[] and instruct ObjectDB to use soft reference for its Level One (L1) object data cache.  I disable the L2 ... [] and uses a soft reference to make that array eligible for GC when the JVM does a full GC. private ... reference to the byte[] when data needs to be written back to ObjectDB datastore, and a soft reference

Detached Entity Objects

object. Cascading Detach Marking a reference field with CascadeType.DETACH (or CascadeType ... that references an instance of Address, which is another entity class. Due to the CascadeType.DETACH ... when applicable (e.g. to entity objects that the Address object references, if any). Bulk Detach

Deleting JPA Entity Objects

that modify the database require an active transaction. Cascading Remove Marking a reference field ... entity class contains an address field that references an instance of Address ... object references, if any). Orphan Removal JPA 2 supports an additional and more aggressive remove

Update Entity references if we change the type of an entity

. As example (like in the attached example): We have an EntityA that have a reference to an EntityB ... , because it's possible that many other entities have just a ID based reference with a simple 'int' field to this element. And we thought that also the real references are based on the ID. This step