anthill.storage
Interface GenericStorage

All Superinterfaces:

Clearable, ResourceManager, Storage

All Known Subinterfaces:

QueryStorage

All Known Implementing Classes:

CmsStorage, LRUKeyStorage, LRUQueryStorage, MemoryStorage, UrlStorage, UrlStorage, UrlStorage

public interface GenericStorage

extends Storage

The GenericStorage represents a generic storage which enforce a simple policy based on a maximum capacity. It contains methods to add, remove and get resources from the storage. You may also inspect the content of the storage using the iterator and check its capacity and usage.

Version:

$Revision: 1.8 $

Author:

Alberto Montresor

, Hein Meling

Field Summary

Fields inherited from interface anthill.storage.Storage

DOC_STORAGE, PHR_STORAGE, URL_STORAGE

Method Summary

void	addResource(Object key, Resource resource) Adds a resource to the storage and associates it to the specified key.
boolean	containsResource(Object key) Returns true if the resource associated to key is contained in the storage, false otherwise.
long	getCapacity() Returns the initial capacity of this generic storage.
long	getRemainingCapacity() Returns the remaining capacity of this generic storage.
Resource	getResource(Object key) Returns the resource associated with the specified key.
Iterator	iterator() Returns the complete set of resources stored in this storage object using an iterator.
void	removeResource(Object key) Removes the resource associated with the specified key from the storage.

Methods inherited from interface anthill.util.Clearable

clear

Method Detail

getResource

public Resource getResource(Object key)

Returns the resource associated with the specified key. If the key is not associated with any resource, a null value is returned.

Parameters:

key - whose associated resource to retreive.

Returns:

resource with which the specified key is associated.

containsResource

public boolean containsResource(Object key)

Returns true if the resource associated to key is contained in the storage, false otherwise.

Parameters:

key - the key to be searched

Returns:

true if the resource associated to key is contained in the storage

addResource

public void addResource(Object key,
                        Resource resource)
                 throws CapacityException

Adds a resource to the storage and associates it to the specified key. If the remaining capacity of the storage is not sufficient to store the resource, a CapacityException is thrown containing information about the remaining capacity. Method getContentLength() may be invoked on the resource to determine the amount of space required by the resource. In order to be stored on persistent storage, resource must implement the Serializable interface.

Parameters:

key - the key identifying the resource

resource - the resource to be added

Throws:

CapacityException - raised if the given resource object exceeds the total available capacity for this storage.

removeResource

public void removeResource(Object key)

Removes the resource associated with the specified key from the storage.

Parameters:

key - the identifier of the resource to be removed

iterator

public Iterator iterator()

Returns the complete set of resources stored in this storage object using an iterator.

Returns:

iterator representing this storage object, allowing to inspect its content.

getCapacity

public long getCapacity()

Returns the initial capacity of this generic storage.

getRemainingCapacity

public long getRemainingCapacity()

Returns the remaining capacity of this generic storage.