EclipseLink/Development/JPA 2.0/cache usaged

JPA 2.0: Cache Usage Settings

JPA 2.0 Root | bug 277039

Date	Committer(s)	Description
Feb 2, 2009	gyorke	Initial feature template

Summary

The specification introduces cache usage controls in JPA 2.0. Users can use settings on the Entity and Query hints to control how the cache should be used. There are separate settings for how a provider can use the cache for query results and when the cache should be updated with database query results.

// From JPA 2.0 Specification
public enum CacheRetrieveMode {
 
    /**
     * Read entity data from the cache: this is
     * the default behavior.
     */
    USE,
 
    /**
     * Bypass the cache: get data directly from
     * the database.
     */
    BYPASS
}
 
public enum CacheStoreMode {
 
    /**
     * Insert/update entity data into cache when read
     * from database and when committed into database:
     * this is the default behavior. Does not force refresh
     * of already cached items when reading from database.
     */
    USE,
 
    /**
     * Don't insert into cache.
     */
    BYPASS,
 
    /**
     * Insert/update entity data into cache when read
     * from database and when committed into database:
     * Forces refresh of cache for items read from database.
     */
    REFRESH
}

// From JPA 2.0 Specification
@Target({TYPE}) @Retention(RUNTIME)
public @interface Cacheable {
boolean value() default true;

Most of this support should already exist at the query level but entity level settings may need to be added. PersistenceUnitInfo class updates. orm.xml and persistence.xml processing and annotation processing will be required

Functional Requirements

• Support specification requirements.
• Default for the "caching element" will be DISABLE_SELECTIVE

Work Estimate

1. Develop model for testing cache usage settings

   approx 3 days

2. Update processing

   approx 3 days

3. Implement Functionality

   approx 3 days