org.mycore.datamodel.ifs
Class MCRFileMetadataManager

java.lang.Object
  org.mycore.datamodel.ifs.MCRFileMetadataManager

public class MCRFileMetadataManager
extends Object

The single instance of this class is used by the other IFS classes to create, retrieve, update or delete the metadata of all MCRFilesystemNode objects in a persistent datastore. The manager holds a cache of all MCRFilesystemNodes most recently used. It creates the MCRFileMetadataStore instance as configured in the MyCoRe properties and hides its usage from the other classes. Configuration properties:

• MCR.IFS.FileMetadataStore.Class: The class that implements the MCRFileMetadataStore interface and that should be used to store the persistent metadata.
• MCR.Persistence.IFS.FileMetadataStore.CacheSize: The size of the cache holding the most recently used MCRFilesystemNodes expressed as maximum number of node objects in the cache.

Version:

$Revision: 13085 $ $Date: 2008-02-06 18:27:24 +0100 (Mi, 06 Feb 2008) $

Author:

Frank Lützenkirchen

See Also:

MCRFilesystemNode, MCRFileMetadataStore

Method Summary

MCRFilesystemNode	buildNode(String type, String ID, String parentID, String ownerID, String name, String label, long size, GregorianCalendar date, String storeID, String storageID, String fctID, String md5, int numchdd, int numchdf, int numchtd, int numchtf) Callback method for internal use by any MCRFileMetadataStore implementation, do not use.
(package private) String	createNodeID() Creates a new, unique ID for each MCRFilesystemNode
(package private) void	deleteNode(String ID) Deletes a MCRFilesystemNode in the persistent MCRFileMetadataStore.
static MCRFileMetadataManager	instance() Returns the single instance of this class to use *
MCRFilesystemNode	retrieveChild(String parentID, String name) Retrieves a child node of a given MCRDirectory node.
(package private) Vector	retrieveChildrenIDs(String ID) Retrieves a list of all IDs of the child MCRFilesystemNodes of a given MCRDirectory.
(package private) MCRFilesystemNode	retrieveNode(String ID) Retrieves the MCRFilesystemNode with the given ID from the persistent MCRFileMetadataStore.
(package private) MCRFilesystemNode	retrieveRootNode(String ownerID) Retrieves the first MCRFilesystemNode found in the persistent MCRFileMetadataStore, that has the given owner ID.
(package private) void	storeNode(MCRFilesystemNode node) Creates or updates the data of the MCRFilesystemNode in the persistent MCRFileMetadataStore.

Methods inherited from class java.lang.Object

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

Method Detail

instance

public static MCRFileMetadataManager instance()

Returns the single instance of this class to use *

createNodeID

String createNodeID()

Creates a new, unique ID for each MCRFilesystemNode

storeNode

void storeNode(MCRFilesystemNode node)
         throws MCRPersistenceException

Creates or updates the data of the MCRFilesystemNode in the persistent MCRFileMetadataStore.

Parameters:

node - the MCRFilesystemNode to store

Throws:

MCRPersistenceException

retrieveNode

MCRFilesystemNode retrieveNode(String ID)
                         throws MCRPersistenceException

Retrieves the MCRFilesystemNode with the given ID from the persistent MCRFileMetadataStore.

Parameters:

ID - the unique ID of the MCRFilesystemNode

Returns:

the MCRFilesystemNode with that ID, or null if no such node exists.

Throws:

MCRPersistenceException

retrieveRootNode

MCRFilesystemNode retrieveRootNode(String ownerID)
                             throws MCRPersistenceException

Retrieves the first MCRFilesystemNode found in the persistent MCRFileMetadataStore, that has the given owner ID. This is assumed to be a root node.

Parameters:

ownerID - the ID of the owner of the MCRFilesystemNode to be retrieved

Returns:

the MCRFilesystemNode with that owner, or null if no such node exists.

Throws:

MCRPersistenceException

retrieveChild

public MCRFilesystemNode retrieveChild(String parentID,
                                       String name)
                                throws MCRPersistenceException

Retrieves a child node of a given MCRDirectory node.

Parameters:

parentID - the ID of the parent MCRDirectory

name - the file name of the child in that directory

Returns:

the child MCRFilesystemNode, or null, if no such child exists

Throws:

MCRPersistenceException

buildNode

public MCRFilesystemNode buildNode(String type,
                                   String ID,
                                   String parentID,
                                   String ownerID,
                                   String name,
                                   String label,
                                   long size,
                                   GregorianCalendar date,
                                   String storeID,
                                   String storageID,
                                   String fctID,
                                   String md5,
                                   int numchdd,
                                   int numchdf,
                                   int numchtd,
                                   int numchtf)
                            throws MCRPersistenceException

Callback method for internal use by any MCRFileMetadataStore implementation, do not use. Builds a MCRFilesystemNode object from the raw data that is retrieved from the persistent store, or uses the existing copy in the MCRCache instance.

Throws:

MCRPersistenceException

retrieveChildrenIDs

Vector retrieveChildrenIDs(String ID)
                     throws MCRPersistenceException

Retrieves a list of all IDs of the child MCRFilesystemNodes of a given MCRDirectory.

Parameters:

ID - the ID of the parent MCRDirectory

Returns:

a Vector of String objects containing the IDs of all children of that MCRDirectory

Throws:

MCRPersistenceException

deleteNode

void deleteNode(String ID)
          throws MCRPersistenceException

Deletes a MCRFilesystemNode in the persistent MCRFileMetadataStore.

Parameters:

ID - the ID of the node to delete from the store

Throws:

MCRPersistenceException