ptdb.kernel.database

Class CacheManager

java.lang.Object

ptdb.kernel.database.CacheManager

public class CacheManager
extends java.lang.Object

The class that interfaces with the model cache. Cached models need not be constructed with references. They are completely self-contained. Use of a cache saves time when loading models that contain many references. When a model is loaded from the database, the complete model is added to the cache. When a model is saved, the entry of that model and all other models that reference it are removed from the cache.

Since:

Ptolemy II 10.0

Version:

$Id$

Author:

Lyle Holsinger

Pt.AcceptedRating:

Red (lholsing)

Pt.ProposedRating:

Red (lholsing)

Constructor Summary

Constructors

Constructor and Description
CacheManager()

Method Summary

Modifier and Type	Method and Description
static XMLDBModel	loadFromCache(java.lang.String modelName) Given a model name, load a model from the cache.
static boolean	removeFromCache(java.util.ArrayList<XMLDBModel> modelsToRemove) Remove a set of models from the cache.
static void	updateCache(java.util.HashMap assemblies) Update a collection of models in the cache.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CacheManager

public CacheManager()

Method Detail

removeFromCache

public static boolean removeFromCache(java.util.ArrayList<XMLDBModel> modelsToRemove)
                               throws DBConnectionException,
                                      DBExecutionException

Remove a set of models from the cache.

Parameters:

modelsToRemove - An ArrayList of XMLDBModel objects. The names of these are used to remove the respective MoMLs from the cache.

Returns:

True if the removal was successful. False if it was not.

Throws:

DBConnectionException - Thrown if a problem occurs with the cache connection.

DBExecutionException - Thrown if a problem occurs removing a model from the cache.

loadFromCache

public static XMLDBModel loadFromCache(java.lang.String modelName)
                                throws DBConnectionException,
                                       DBExecutionException

Given a model name, load a model from the cache.

Parameters:

modelName - The name of the model to be loaded form the cache.

Returns:

An XMLDBModel populated with the model's MoML string.

Throws:

DBConnectionException - Thrown if a problem occurs with the cache connection.

DBExecutionException - Thrown if a problem occurs retrieving the MoML from the database.

updateCache

public static void updateCache(java.util.HashMap assemblies)
                        throws DBConnectionException,
                               DBExecutionException

Update a collection of models in the cache. If a model is not in the cache, add it. If it is, update it.

Parameters:

assemblies - A HashMap that maps a collection of models names to their respective MoML strings. These are the models to be updated in the cache.

Throws:

DBConnectionException - Thrown if a problem occurs with the cache connection.

DBExecutionException - Thrown if a problem occurs updating the cache.