/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors. All rights reserved.
*/
package org.pentaho.reporting.libraries.resourceloader;
import java.net.URL;
import java.util.Map;
/**
* A resource loader knows how to get binary rawdata from a location specified by an resource key. A resource key is a
* wrapper around any kind of data that is suitable to identify a resource location. The resource key can also hold
* configuration data for the factory.
* <p/>
* If the storage system is hierarchical, a new resource key can be derived from a given path-string.
*
* @author Thomas Morgner
*/
public interface ResourceLoader {
/**
* Checks, whether this resource loader implementation was responsible for creating this key.
*
* @param key the key that should be tested.
* @return true, if the key is supported.
*/
public boolean isSupportedKey( ResourceKey key );
/**
* Creates a new resource key from the given object and the factory keys.
*
* @param value the key value.
* @param factoryKeys optional parameter map (can be null).
* @return the created key or null, if the format was not recognized.
* @throws ResourceKeyCreationException if creating the key failed.
*/
public ResourceKey createKey( Object value,
Map factoryKeys )
throws ResourceKeyCreationException;
/**
* Derives a new resource key from the given key. If neither a path nor new factory-keys are given, the parent key is
* returned.
*
* @param parent the parent
* @param path the derived path (can be null).
* @param factoryKeys the optional factory keys (can be null).
* @return the derived key.
* @throws ResourceKeyCreationException if the key cannot be derived for any reason.
*/
public ResourceKey deriveKey( ResourceKey parent,
String path,
Map factoryKeys )
throws ResourceKeyCreationException;
/**
* Loads the binary data represented by this key.
*
* @param key
* @return
* @throws ResourceLoadingException
*/
public ResourceData load( final ResourceKey key )
throws ResourceLoadingException;
/**
* Generates a <code>URL</code> version of the supplied <code>ResourceKey</code>.
*
* @param key the <code>ResourceKey</code> from which a <code>URL</code> will be created
* @return the URL representation of the <code>ResourceKey</code>
*/
public URL toURL( ResourceKey key );
/**
* Determines if the resource loader is capable of deserializing the serialized version of the ResourceKey.
*
* @param data the serialized version of the resource key
* @return <code>true</code> if this <code>ResourceLoader</code> is capable of deserializing the serialized version of
* this resource key, <code>false</code> otherwise.
*/
public boolean isSupportedDeserializer( final String data );
/**
* Serializes the resource key to a String representation which can be recreated using the
* <code>deserialize(ResourceKey)<code> method.
*
* @param bundleKey
* @param key
* @return a <code>String<code> which is a serialized version of the <code>ResourceKey</code>
* @throws ResourceException indicates an error serializing the resource key
*/
public String serialize( final ResourceKey bundleKey, final ResourceKey key ) throws ResourceException;
/**
* Creates a <code>ResourceKey</code> based off the <code>String</code> representation of the key. The
* <code>String</code> should have been created using the <code>serialize</code> method.
*
* @param bundleKey
* @param stringKey the <code>String</code> representation of the <code>ResourceKey</code> @return a
* <code>ResourceKey</code> which matches the <code>String</code> representation
* @throws ResourceKeyCreationException indicates an error occurred in the creation or deserialization of the
* <code>ResourceKey</code>
*/
public ResourceKey deserialize( final ResourceKey bundleKey, final String stringKey )
throws ResourceKeyCreationException;
}