http://www.avaje.org/java8-parent/persistence-api: For open source java artifacts.
  • Rob Bygrave 
/*
 * Copyright (c) 2008, 2009, 2011 Oracle, Inc. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.  The Eclipse Public License is available
 * at http://www.eclipse.org/legal/epl-v10.html and the Eclipse Distribution License
 * is available at http://www.eclipse.org/org/documents/edl-v10.php.
 */
package javax.persistence;


Interface used to interact with the second-level cache.
If a cache is not in use, the methods of this interface have
no effect, except for contains, which returns false.

Since:Java Persistence 2.0
/**
 * Interface used to interact with the second-level cache.
 * If a cache is not in use, the methods of this interface have
 * no effect, except for <code>contains</code>, which returns false.
 *
 * @since Java Persistence 2.0
 */
public interface Cache {

  
Whether the cache contains data for the given entity.

Params:
  • cls –        entity class
  • primaryKey – primary key
Returns:boolean indicating whether the entity is in the cache
/**
   * Whether the cache contains data for the given entity.
   *
   * @param cls        entity class
   * @param primaryKey primary key
   * @return boolean indicating whether the entity is in the cache
   */
  public boolean contains(Class cls, Object primaryKey);

  
Remove the data for the given entity from the cache.

Params:
  • cls –        entity class
  • primaryKey – primary key
/**
   * Remove the data for the given entity from the cache.
   *
   * @param cls        entity class
   * @param primaryKey primary key
   */
  public void evict(Class cls, Object primaryKey);

  
Remove the data for entities of the specified class (and its
subclasses) from the cache.

Params:
  • cls – entity class
/**
   * Remove the data for entities of the specified class (and its
   * subclasses) from the cache.
   *
   * @param cls entity class
   */
  public void evict(Class cls);

  
Clear the cache.

/**
   * Clear the cache.
   */
  public void evictAll();

  
Return an object of the specified type to allow access to the provider-specific API.


If the provider's Cache implementation does not support the specified class, the
PersistenceException is thrown.

Params:
  • cls – the class of the object to be returned. This is normally either the
           underlying Cache implementation class or an interface that it implements.
Throws:
Returns:an instance of the specified class
/**
   * Return an object of the specified type to allow access to the provider-specific API.
   * <p>
   * If the provider's Cache implementation does not support the specified class, the
   * PersistenceException is thrown.
   *
   * @param cls the class of the object to be returned. This is normally either the
   *            underlying Cache implementation class or an interface that it implements.
   * @return an instance of the specified class
   * @throws PersistenceException if the provider does not support the call
   */
  public <T> T unwrap(Class<T> cls);

}