Package org.pentaho.reporting.libraries.resourceloader

Interface ResourceLoader

All Known Implementing Classes:

ClassloaderResourceLoader, FileObjectResourceLoader, FileResourceLoader, RawResourceLoader, URLResourceLoader, ZipResourceLoader

public interface ResourceLoader

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.

If the storage system is hierarchical, a new resource key can be derived from a given path-string.

Author:

Thomas Morgner

Method Summary

Modifier and Type	Method	Description
ResourceKey	createKey(Object value, Map factoryKeys)	Creates a new resource key from the given object and the factory keys.
ResourceKey	deriveKey(ResourceKey parent, String path, Map factoryKeys)	Derives a new resource key from the given key.
ResourceKey	deserialize(ResourceKey bundleKey, String stringKey)	Creates a ResourceKey based off the String representation of the key.
boolean	isSupportedDeserializer(String data)	Determines if the resource loader is capable of deserializing the serialized version of the ResourceKey.
boolean	isSupportedKey(ResourceKey key)	Checks, whether this resource loader implementation was responsible for creating this key.
ResourceData	load(ResourceKey key)	Loads the binary data represented by this key.
String	serialize(ResourceKey bundleKey, ResourceKey key)	Serializes the resource key to a String representation which can be recreated using the deserialize(ResourceKey) method.
URL	toURL(ResourceKey key)	Generates a URL version of the supplied ResourceKey.

Method Detail

isSupportedKey

boolean isSupportedKey(ResourceKey key)

Checks, whether this resource loader implementation was responsible for creating this key.

Parameters:

key - the key that should be tested.

Returns:

true, if the key is supported.

createKey

ResourceKey createKey(Object value,
                      Map factoryKeys)
               throws ResourceKeyCreationException

Creates a new resource key from the given object and the factory keys.

Parameters:

value - the key value.

factoryKeys - optional parameter map (can be null).

Returns:

the created key or null, if the format was not recognized.

Throws:

ResourceKeyCreationException - if creating the key failed.

deriveKey

ResourceKey deriveKey(ResourceKey parent,
                      String path,
                      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.

Parameters:

parent - the parent

path - the derived path (can be null).

factoryKeys - the optional factory keys (can be null).

Returns:

the derived key.

Throws:

ResourceKeyCreationException - if the key cannot be derived for any reason.

load

ResourceData load(ResourceKey key)
           throws ResourceLoadingException

Loads the binary data represented by this key.

Parameters:

key -

Returns:

Throws:

ResourceLoadingException

toURL

URL toURL(ResourceKey key)

Generates a URL version of the supplied ResourceKey.

Parameters:

key - the ResourceKey from which a URL will be created

Returns:

the URL representation of the ResourceKey

isSupportedDeserializer

boolean isSupportedDeserializer(String data)

Determines if the resource loader is capable of deserializing the serialized version of the ResourceKey.

Parameters:

data - the serialized version of the resource key

Returns:

true if this ResourceLoader is capable of deserializing the serialized version of this resource key, false otherwise.

serialize

String serialize(ResourceKey bundleKey,
                 ResourceKey key)
          throws ResourceException

Serializes the resource key to a String representation which can be recreated using the deserialize(ResourceKey) method.

Parameters:

bundleKey -

key -

Returns:

a String which is a serialized version of the ResourceKey

Throws:

ResourceException - indicates an error serializing the resource key

deserialize

ResourceKey deserialize(ResourceKey bundleKey,
                        String stringKey)
                 throws ResourceKeyCreationException

Creates a ResourceKey based off the String representation of the key. The String should have been created using the serialize method.

Parameters:

bundleKey -

stringKey - the String representation of the ResourceKey @return a ResourceKey which matches the String representation

Throws:

ResourceKeyCreationException - indicates an error occurred in the creation or deserialization of the ResourceKey