com.google.clearsilver.jsilver.resourceloader

Class CompositeResourceLoader

java.lang.Object

com.google.clearsilver.jsilver.resourceloader.CompositeResourceLoader

All Implemented Interfaces:

ResourceLoader

public class CompositeResourceLoader
extends Object
implements ResourceLoader

ResourceLoader composed of other ResourceLoaders. When a resource is loaded, it will search through each ResourceLoader until it finds something.

See Also:

ResourceLoader

Constructor Summary

Constructors

Constructor and Description
CompositeResourceLoader(Iterable<ResourceLoader> loaders)
CompositeResourceLoader(ResourceLoader... loaders)

Method Summary

Methods

Modifier and Type	Method and Description
void	add(ResourceLoader loader)
void	close(Reader reader) Close the reader.
Object	getKey(String filename) We return the filename as the key of uniqueness as we assume that if this CompositeResourceLoader is in use, then there won't be another ResourceLoader that we are competing against.
Object	getResourceVersionId(String filename) Return the first non-null version identifier found among the ResourceLoaders, using the same search order as open(String).
Reader	open(String name) Open a resource.
Reader	openOrFail(String name) Open a resource or throw an exception if no such resource is found.

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeResourceLoader

public CompositeResourceLoader(Iterable<ResourceLoader> loaders)

CompositeResourceLoader

public CompositeResourceLoader(ResourceLoader... loaders)

Method Detail

add

public void add(ResourceLoader loader)

open

public Reader open(String name)
            throws IOException

Description copied from interface: ResourceLoader

Open a resource. If this resource is not found, null should be returned. The caller of this method is guaranteed to call ResourceLoader.close(Reader) when done with the reader.

Specified by:

open in interface ResourceLoader

Parameters:

name - the name of the resource

Returns:

Reader, or null if not found.

Throws:

IOException - if resource fails to open

openOrFail

public Reader openOrFail(String name)
                  throws JSilverTemplateNotFoundException,
                         IOException

Description copied from interface: ResourceLoader

Open a resource or throw an exception if no such resource is found. The caller of this method is guaranteed to call ResourceLoader.close(Reader) when done with the reader.

Specified by:

openOrFail in interface ResourceLoader

Parameters:

name - the name of the resource

Returns:

Reader, or null if not found.

Throws:

JSilverTemplateNotFoundException - if resource is not found

IOException - if resource fails to open

close

public void close(Reader reader)
           throws IOException

Description copied from interface: ResourceLoader

Close the reader. Allows ResourceLoader to perform any additional clean up.

Specified by:

close in interface ResourceLoader

Parameters:

reader - the reader to close

Throws:

IOException - if reader fasils to close

getKey

public Object getKey(String filename)

We return the filename as the key of uniqueness as we assume that if this CompositeResourceLoader is in use, then there won't be another ResourceLoader that we are competing against. If we did need to worry about it we would want to prepend the key from above.

Specified by:

getKey in interface ResourceLoader

Parameters:

filename - the name we want to identify

Returns:

unique identifier

getResourceVersionId

public Object getResourceVersionId(String filename)

Return the first non-null version identifier found among the ResourceLoaders, using the same search order as open(String).

Specified by:

getResourceVersionId in interface ResourceLoader

Parameters:

filename - the name of the resource to check for resources

Returns:

unique identifier for the current version of the resource or null if the resource cannot be found