org.springframework.core.io

Class DefaultResourceLoader

java.lang.Object

org.springframework.core.io.DefaultResourceLoader

All Implemented Interfaces:

ResourceLoader

Direct Known Subclasses:

AbstractApplicationContext, ClassRelativeResourceLoader, FileSystemResourceLoader, ServletContextResourceLoader

public class DefaultResourceLoader
extends Object
implements ResourceLoader

Default implementation of the ResourceLoader interface. Used by ResourceEditor, and serves as base class for AbstractApplicationContext. Can also be used standalone.

Will return a UrlResource if the location value is a URL, and a ClassPathResource if it is a non-URL path or a "classpath:" pseudo-URL.

Since:

10.03.2004

Author:

Juergen Hoeller

See Also:

FileSystemResourceLoader, ClassPathXmlApplicationContext

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	DefaultResourceLoader.ClassPathContextResource ClassPathResource that explicitly expresses a context-relative path through implementing the ContextResource interface.

Field Summary

Fields inherited from interface org.springframework.core.io.ResourceLoader

CLASSPATH_URL_PREFIX

Constructor Summary

Constructors

Constructor and Description
DefaultResourceLoader() Create a new DefaultResourceLoader.
DefaultResourceLoader(ClassLoader classLoader) Create a new DefaultResourceLoader.

Method Summary

Modifier and Type	Method and Description
void	addProtocolResolver(ProtocolResolver resolver) Register the given resolver with this resource loader, allowing for additional protocols to be handled.
void	clearResourceCaches() Clear all resource caches in this resource loader.
ClassLoader	getClassLoader() Return the ClassLoader to load class path resources with.
Collection<ProtocolResolver>	getProtocolResolvers() Return the collection of currently registered protocol resolvers, allowing for introspection as well as modification.
Resource	getResource(String location) Return a Resource handle for the specified resource location.
protected Resource	getResourceByPath(String path) Return a Resource handle for the resource at the given path.
<T> Map<Resource,T>	getResourceCache(Class<T> valueType) Obtain a cache for the given value type, keyed by Resource.
void	setClassLoader(ClassLoader classLoader) Specify the ClassLoader to load class path resources with, or null for using the thread context class loader at the time of actual resource access.

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultResourceLoader

public DefaultResourceLoader()

Create a new DefaultResourceLoader.

ClassLoader access will happen using the thread context class loader at the time of actual resource access (since 5.3). For more control, pass a specific ClassLoader to DefaultResourceLoader(ClassLoader).

See Also:

Thread.getContextClassLoader()

DefaultResourceLoader

public DefaultResourceLoader(@Nullable
                             ClassLoader classLoader)

Create a new DefaultResourceLoader.

Parameters:

classLoader - the ClassLoader to load class path resources with, or null for using the thread context class loader at the time of actual resource access

Method Detail

setClassLoader

public void setClassLoader(@Nullable
                           ClassLoader classLoader)

Specify the ClassLoader to load class path resources with, or null for using the thread context class loader at the time of actual resource access.

The default is that ClassLoader access will happen using the thread context class loader at the time of actual resource access (since 5.3).

getClassLoader

@Nullable
public ClassLoader getClassLoader()

Return the ClassLoader to load class path resources with.

Will get passed to ClassPathResource's constructor for all ClassPathResource objects created by this resource loader.

Specified by:

getClassLoader in interface ResourceLoader

Returns:

the ClassLoader (only null if even the system ClassLoader isn't accessible)

See Also:

ClassPathResource

addProtocolResolver

public void addProtocolResolver(ProtocolResolver resolver)

Register the given resolver with this resource loader, allowing for additional protocols to be handled.

Any such resolver will be invoked ahead of this loader's standard resolution rules. It may therefore also override any default rules.

Since:

4.3

See Also:

getProtocolResolvers()

getProtocolResolvers

public Collection<ProtocolResolver> getProtocolResolvers()

Return the collection of currently registered protocol resolvers, allowing for introspection as well as modification.

Since:

4.3

getResourceCache

public <T> Map<Resource,T> getResourceCache(Class<T> valueType)

Obtain a cache for the given value type, keyed by Resource.

Parameters:

valueType - the value type, e.g. an ASM MetadataReader

Returns:

the cache Map, shared at the ResourceLoader level

Since:

5.0

clearResourceCaches

public void clearResourceCaches()

Clear all resource caches in this resource loader.

Since:

5.0

See Also:

getResourceCache(java.lang.Class<T>)

getResource

public Resource getResource(String location)

Description copied from interface: ResourceLoader

Return a Resource handle for the specified resource location.

The handle should always be a reusable resource descriptor, allowing for multiple InputStreamSource.getInputStream() calls.

• Must support fully qualified URLs, e.g. "file:C:/test.dat".
• Must support classpath pseudo-URLs, e.g. "classpath:test.dat".
• Should support relative file paths, e.g. "WEB-INF/test.dat". (This will be implementation-specific, typically provided by an ApplicationContext implementation.)

Note that a Resource handle does not imply an existing resource; you need to invoke Resource.exists() to check for existence.

Specified by:

getResource in interface ResourceLoader

Parameters:

location - the resource location

Returns:

a corresponding Resource handle (never null)

See Also:

ResourceLoader.CLASSPATH_URL_PREFIX, Resource.exists(), InputStreamSource.getInputStream()

getResourceByPath

protected Resource getResourceByPath(String path)

Return a Resource handle for the resource at the given path.

The default implementation supports class path locations. This should be appropriate for standalone implementations but can be overridden, e.g. for implementations targeted at a Servlet container.

Parameters:

path - the path to the resource

Returns:

the corresponding Resource handle

See Also:

ClassPathResource, FileSystemXmlApplicationContext.getResourceByPath(java.lang.String), AbstractRefreshableWebApplicationContext.getResourceByPath(java.lang.String)