Package org.apache.velocity.runtime.resource

Class ResourceManagerImpl

java.lang.Object

org.apache.velocity.runtime.resource.ResourceManagerImpl

All Implemented Interfaces:

ResourceManager

public class ResourceManagerImpl
extends Object
implements ResourceManager

Class to manage the text resource for the Velocity Runtime.

Version:

$Id$

Author:

Will Glass-Husain, Jason van Zyl, Paulo Gaspar, Geir Magnusson Jr., Henning P. Schmiedehausen

Field Summary

Fields

Modifier and Type	Field	Description
protected ResourceCache	globalCache	Object implementing ResourceCache to be our resource manager's Resource cache.
protected org.slf4j.Logger	log	Logging.
static int	RESOURCE_CONTENT	A static content resource.
static int	RESOURCE_TEMPLATE	A template resources.
protected List<ResourceLoader>	resourceLoaders	The List of templateLoaders that the Runtime will use to locate the InputStream source of a template.
protected RuntimeServices	rsvc	The internal RuntimeServices object.

Constructor Summary

Constructors

Constructor	Description
ResourceManagerImpl()

Method Summary

Modifier and Type	Method	Description
protected Resource	createResource(String resourceName, int resourceType)	Create a new Resource of the specified type.
String	getLoaderNameForResource(String resourceName)	Determines if a template exists, and returns name of the loader that provides it.
Resource	getResource(String resourceName, int resourceType, String encoding)	Gets the named resource.
void	initialize(RuntimeServices rs)	Initialize the ResourceManager.
protected Resource	loadResource(String resourceName, int resourceType, String encoding)	Loads a resource from the current set of resource loaders.
protected Resource	refreshResource(Resource resource, String encoding)	Takes an existing resource, and 'refreshes' it.

Methods inherited from class java.lang.Object

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

Field Detail

RESOURCE_TEMPLATE

public static final int RESOURCE_TEMPLATE

A template resources.

See Also:

Constant Field Values

RESOURCE_CONTENT

public static final int RESOURCE_CONTENT

A static content resource.

See Also:

Constant Field Values

globalCache

protected ResourceCache globalCache

Object implementing ResourceCache to be our resource manager's Resource cache.

resourceLoaders

protected final List<ResourceLoader> resourceLoaders

The List of templateLoaders that the Runtime will use to locate the InputStream source of a template.

rsvc

protected RuntimeServices rsvc

The internal RuntimeServices object.

log

protected org.slf4j.Logger log

Logging.

Constructor Detail

ResourceManagerImpl

public ResourceManagerImpl()

Method Detail

initialize

public void initialize(RuntimeServices rs)

Initialize the ResourceManager.

Specified by:

initialize in interface ResourceManager

Parameters:

rs - The Runtime Services object which is associated with this Resource Manager.

getResource

public Resource getResource(String resourceName,
                            int resourceType,
                            String encoding)
                     throws ResourceNotFoundException,
                            ParseErrorException

Gets the named resource. Returned class type corresponds to specified type (i.e. Template to RESOURCE_TEMPLATE). This method is now unsynchronized which requires that ResourceCache implementations be thread safe (as the default is).

Specified by:

getResource in interface ResourceManager

Parameters:

resourceName - The name of the resource to retrieve.

resourceType - The type of resource (RESOURCE_TEMPLATE, RESOURCE_CONTENT, etc.).

encoding - The character encoding to use.

Returns:

Resource with the template parsed and ready.

Throws:

ResourceNotFoundException - if template not found from any available source.

ParseErrorException - if template cannot be parsed due to syntax (or other) error.

createResource

protected Resource createResource(String resourceName,
                                  int resourceType)

Create a new Resource of the specified type.

Parameters:

resourceName - The name of the resource to retrieve.

resourceType - The type of resource (RESOURCE_TEMPLATE, RESOURCE_CONTENT, etc.).

Returns:

new instance of appropriate resource type

Since:

1.6

loadResource

protected Resource loadResource(String resourceName,
                                int resourceType,
                                String encoding)
                         throws ResourceNotFoundException,
                                ParseErrorException

Loads a resource from the current set of resource loaders.

Parameters:

resourceName - The name of the resource to retrieve.

resourceType - The type of resource (RESOURCE_TEMPLATE, RESOURCE_CONTENT, etc.).

encoding - The character encoding to use.

Returns:

Resource with the template parsed and ready.

Throws:

ResourceNotFoundException - if template not found from any available source.

ParseErrorException - if template cannot be parsed due to syntax (or other) error.

refreshResource

protected Resource refreshResource(Resource resource,
                                   String encoding)
                            throws ResourceNotFoundException,
                                   ParseErrorException

Takes an existing resource, and 'refreshes' it. This generally means that the source of the resource is checked for changes according to some cache/check algorithm and if the resource changed, then the resource data is reloaded and re-parsed.

Parameters:

resource - resource to refresh

encoding - character encoding of the resource to refresh.

Returns:

resource

Throws:

ResourceNotFoundException - if template not found from current source for this Resource

ParseErrorException - if template cannot be parsed due to syntax (or other) error.

getLoaderNameForResource

public String getLoaderNameForResource(String resourceName)

Determines if a template exists, and returns name of the loader that provides it. This is a slightly less hokey way to support the Velocity.templateExists() utility method, which was broken when per-template encoding was introduced. We can revisit this.

Specified by:

getLoaderNameForResource in interface ResourceManager

Parameters:

resourceName - Name of template or content resource

Returns:

class name of loader than can provide it