org.rapidcontext.core.storage

Class WrappedStorage

java.lang.Object

org.rapidcontext.core.storage.StorableObject

org.rapidcontext.core.storage.Storage

org.rapidcontext.core.storage.WrappedStorage

All Implemented Interfaces:

java.lang.Comparable

Direct Known Subclasses:

PluginUpgradeStorage

public class WrappedStorage
extends Storage

A storage wrapper class. This class allows any storage object to be wrapped and modified or monitored. It is useful when transformations must be applied to the storage results or the data lookup routines (such as for backwards compatibility). This class routes all storage requests unmodified to and from the wrapped storage. It must be subclassed to provide any changes.

Version:

1.0

Author:

Per Cederberg

Field Summary

Fields inherited from class org.rapidcontext.core.storage.Storage

KEY_MOUNT_OVERLAY_PATH, KEY_MOUNT_OVERLAY_PRIO, KEY_MOUNT_PATH, KEY_MOUNT_TIME, KEY_READWRITE, PATH_STORAGE, PATH_STORAGE_CACHE, PATH_STORAGEINFO

Fields inherited from class org.rapidcontext.core.storage.StorableObject

dict, KEY_CLASSNAME, KEY_ID, KEY_TYPE

Constructor Summary

Constructors

Constructor and Description
WrappedStorage(java.lang.String storageType, Storage wrapped) Creates a new wrapped (or encapsulated) storage.

Method Summary

Modifier and Type	Method and Description
protected void	destroy() Destroys this object.
java.lang.Object	load(Path path) Loads an object from the specified location.
Metadata	lookup(Path path) Searches for an object at the specified location and returns metadata about the object if found.
void	remove(Path path) Removes an object or an index at the specified location.
void	setMountInfo(Path path, boolean readWrite, Path overlay, int prio) Updates the mount information for this storage.
void	store(Path path, java.lang.Object data) Stores an object at the specified location.

Methods inherited from class org.rapidcontext.core.storage.Storage

compareTo, isReadWrite, loadAll, localPath, lookupAll, mountOverlayPath, mountOverlayPrio, mountTime, path

Methods inherited from class org.rapidcontext.core.storage.StorableObject

activate, id, init, isActive, isModified, passivate, serialize, toString, type

Methods inherited from class java.lang.Object

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

Constructor Detail

WrappedStorage

public WrappedStorage(java.lang.String storageType,
                      Storage wrapped)

Creates a new wrapped (or encapsulated) storage.

Parameters:

storageType - the storage type name

wrapped - the encapsulated storage

Method Detail

destroy

protected void destroy()
                throws StorageException

Destroys this object. This method is used to free any resources used when this object is no longer used. This method is called when an object is removed from the in-memory storage (object cache).

Overrides:

destroy in class StorableObject

Throws:

StorageException - if the destruction failed

setMountInfo

public void setMountInfo(Path path,
                         boolean readWrite,
                         Path overlay,
                         int prio)

Updates the mount information for this storage. This method will update the mount time to the current timestamp.

Overrides:

setMountInfo in class Storage

Parameters:

path - the mount path (or storage root path)

readWrite - the storage read-write flag

overlay - the mount overlay path

prio - the mount overlay priority

lookup

public Metadata lookup(Path path)

Searches for an object at the specified location and returns metadata about the object if found. The path may locate either an index or a specific object.

Specified by:

lookup in class Storage

Parameters:

path - the storage location

Returns:

the metadata for the object, or null if not found

load

public java.lang.Object load(Path path)

Loads an object from the specified location. The path may locate either an index or a specific object. In case of an index, the data returned is an index dictionary listing of all objects in it.

Specified by:

load in class Storage

Parameters:

path - the storage location

Returns:

the data read, or null if not found

store

public void store(Path path,
                  java.lang.Object data)
           throws StorageException

Stores an object at the specified location. The path must locate a particular object or file, since direct manipulation of indices is not supported. Any previous data at the specified path will be overwritten or removed. Note that only dictionaries and files can be stored in a file storage.

Specified by:

store in class Storage

Parameters:

path - the storage location

data - the data to store

Throws:

StorageException - if the data couldn't be written

remove

public void remove(Path path)
            throws StorageException

Removes an object or an index at the specified location. If the path refers to an index, all contained objects and indices will be removed recursively.

Specified by:

remove in class Storage

Parameters:

path - the storage location

Throws:

StorageException - if the data couldn't be removed