org.rapidcontext.core.storage

Class ZipStorage

java.lang.Object

org.rapidcontext.core.storage.StorableObject

org.rapidcontext.core.storage.Storage

org.rapidcontext.core.storage.ZipStorage

All Implemented Interfaces:

java.lang.Comparable

public class ZipStorage
extends Storage

A persistent data storage and retrieval handler based on a ZIP file. This class will read both Java property files and binary files depending on the file extension. The property files are converted to dictionary object on retrieval.

Note: This storage is read-only. Unpack the ZIP file and use a DirStorage for read-write access.

Version:

1.0

Author:

Per Cederberg

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.HashMap	entries The ZIP entries and index map.
static java.lang.String	KEY_FILE The dictionary key for the ZIP file location.
protected java.util.zip.ZipFile	zip The ZIP file used for locating resources.

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
ZipStorage(java.io.File zipFile) Creates a new read-only ZIP file storage.

Method Summary

Modifier and Type	Method and Description
void	destroy() Destroys this object.
java.io.File	file() Returns the ZIP file being read by this storage.
void	init() Initializes 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	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, setMountInfo

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

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

Methods inherited from class java.lang.Object

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

Field Detail

KEY_FILE

public static final java.lang.String KEY_FILE

The dictionary key for the ZIP file location. The value stored is a file object.

See Also:

Constant Field Values

zip

protected java.util.zip.ZipFile zip

The ZIP file used for locating resources.

entries

protected java.util.HashMap entries

The ZIP entries and index map. Indexed by the storage path and linked to either the Index or the ZipEntry objects.

Constructor Detail

ZipStorage

public ZipStorage(java.io.File zipFile)
           throws java.io.IOException

Creates a new read-only ZIP file storage.

Parameters:

zipFile - the ZIP file to use

Throws:

java.io.IOException - if the ZIP couldn't be opened properly

Method Detail

init

public void init()

Initializes this object. This method locates all the ZIP file entries and creates all the indexes.

Overrides:

init in class StorableObject

destroy

public void destroy()
             throws StorageException

Destroys this object. This method is used to free any resources used when this object is no longer used.

Overrides:

destroy in class StorableObject

Throws:

StorageException - if the destruction failed

file

public java.io.File file()

Returns the ZIP file being read by this storage.

Returns:

the ZIP file being read

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