org.eclipse.jetty.util.resource

Class Resource

java.lang.Object

org.eclipse.jetty.util.resource.Resource

All Implemented Interfaces:

Closeable, AutoCloseable, ResourceFactory

Direct Known Subclasses:

EmptyResource, FileResource, PathResource, ResourceCollection, URLResource

public abstract class Resource
extends Object
implements ResourceFactory, Closeable

Abstract resource class.

This class provides a resource abstraction, where a resource may be a file, a URL or an entry in a jar file.

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	__defaultUseCaches

Constructor Summary

Constructors

Constructor and Description
Resource()

Method Summary

Methods

Modifier and Type	Method and Description
abstract Resource	addPath(String path) Returns the resource contained inside the current resource with the given name.
abstract void	close() Release any temporary resources held by the resource.
void	copyTo(File destination)
abstract boolean	delete() Deletes the given resource
String	encode(String uri) Deprecated.
abstract boolean	exists() Returns true if the respresened resource exists.
protected void	finalize()
URI	getAlias()
Collection<Resource>	getAllResources()
Object	getAssociate()
static boolean	getDefaultUseCaches()
abstract File	getFile() Returns an File representing the given resource or NULL if this is not possible.
abstract InputStream	getInputStream() Returns an input stream to the resource
String	getListHTML(String base, boolean parent) Get the resource list as a HTML directory listing.
abstract String	getName() Returns the name of the resource
abstract ReadableByteChannel	getReadableByteChannel() Returns an readable bytechannel to the resource or null if one is not available.
Resource	getResource(String path) Get a resource from within this resource.
URI	getURI() Returns an URI representing the given resource
abstract URL	getURL() Returns an URL representing the given resource
String	getWeakETag()
abstract boolean	isContainedIn(Resource r)
static boolean	isContainedIn(Resource r, Resource containingResource)
abstract boolean	isDirectory() Returns true if the respresenetd resource is a container/directory.
abstract long	lastModified() Returns the last modified time
abstract long	length() Return the length of the resource
abstract String[]	list() Returns a list of resource names contained in the given resource The resource names are not URL encoded.
static Resource	newClassPathResource(String resource) Find a classpath resource.
static Resource	newClassPathResource(String name, boolean useCaches, boolean checkParents) Find a classpath resource.
static Resource	newResource(File file)
static Resource	newResource(String resource) Construct a resource from a string.
static Resource	newResource(String resource, boolean useCaches) Construct a resource from a string.
static Resource	newResource(URI uri) Construct a resource from a uri.
static Resource	newResource(URL url) Construct a resource from a url.
static Resource	newSystemResource(String resource) Construct a system resource from a string.
void	release() Deprecated. use close()
abstract boolean	renameTo(Resource dest) Rename the given resource
void	setAssociate(Object o)
static void	setDefaultUseCaches(boolean useCaches) Change the default setting for url connection caches.
static URL	toURL(File file) Generate a properly encoded URL from a File instance.
void	writeTo(OutputStream out, long start, long count)

Methods inherited from class java.lang.Object

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

Field Detail

__defaultUseCaches

public static boolean __defaultUseCaches

Constructor Detail

Resource

public Resource()

Method Detail

setDefaultUseCaches

public static void setDefaultUseCaches(boolean useCaches)

Change the default setting for url connection caches. Subsequent URLConnections will use this default.

Parameters:

useCaches -

getDefaultUseCaches

public static boolean getDefaultUseCaches()

newResource

public static Resource newResource(URI uri)
                            throws MalformedURLException

Construct a resource from a uri.

Parameters:

uri - A URI.

Returns:

A Resource object.

Throws:

MalformedURLException - Problem accessing URI

newResource

public static Resource newResource(URL url)

Construct a resource from a url.

Parameters:

url - A URL.

Returns:

A Resource object.

newResource

public static Resource newResource(String resource)
                            throws MalformedURLException

Construct a resource from a string.

Parameters:

resource - A URL or filename.

Returns:

A Resource object.

Throws:

MalformedURLException - Problem accessing URI

newResource

public static Resource newResource(String resource,
                   boolean useCaches)
                            throws MalformedURLException

Construct a resource from a string.

Parameters:

resource - A URL or filename.

useCaches - controls URLConnection caching

Returns:

A Resource object.

Throws:

MalformedURLException - Problem accessing URI

newResource

public static Resource newResource(File file)

newSystemResource

public static Resource newSystemResource(String resource)
                                  throws IOException

Construct a system resource from a string. The resource is tried as classloader resource before being treated as a normal resource.

Parameters:

resource - Resource as string representation

Returns:

The new Resource

Throws:

IOException - Problem accessing resource.

newClassPathResource

public static Resource newClassPathResource(String resource)

Find a classpath resource.

newClassPathResource

public static Resource newClassPathResource(String name,
                            boolean useCaches,
                            boolean checkParents)

Find a classpath resource. The Class.getResource(String) method is used to lookup the resource. If it is not found, then the Loader.getResource(Class, String) method is used. If it is still not found, then ClassLoader.getSystemResource(String) is used. Unlike ClassLoader.getSystemResource(String) this method does not check for normal resources.

Parameters:

name - The relative name of the resource

useCaches - True if URL caches are to be used.

checkParents - True if forced searching of parent Classloaders is performed to work around loaders with inverted priorities

Returns:

Resource or null

isContainedIn

public static boolean isContainedIn(Resource r,
                    Resource containingResource)
                             throws MalformedURLException

Throws:

MalformedURLException

finalize

protected void finalize()

Overrides:

finalize in class Object

isContainedIn

public abstract boolean isContainedIn(Resource r)
                               throws MalformedURLException

Throws:

MalformedURLException

release

public final void release()

Deprecated. use close()

Release any temporary resources held by the resource.

close

public abstract void close()

Release any temporary resources held by the resource.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

exists

public abstract boolean exists()

Returns true if the respresened resource exists.

isDirectory

public abstract boolean isDirectory()

Returns true if the respresenetd resource is a container/directory. If the resource is not a file, resources ending with "/" are considered directories.

lastModified

public abstract long lastModified()

Returns the last modified time

length

public abstract long length()

Return the length of the resource

getURL

public abstract URL getURL()

Returns an URL representing the given resource

getURI

public URI getURI()

Returns an URI representing the given resource

getFile

public abstract File getFile()
                      throws IOException

Returns an File representing the given resource or NULL if this is not possible.

Throws:

IOException

getName

public abstract String getName()

Returns the name of the resource

getInputStream

public abstract InputStream getInputStream()
                                    throws IOException

Returns an input stream to the resource

Throws:

IOException

getReadableByteChannel

public abstract ReadableByteChannel getReadableByteChannel()
                                                    throws IOException

Returns an readable bytechannel to the resource or null if one is not available.

Throws:

IOException

delete

public abstract boolean delete()
                        throws SecurityException

Deletes the given resource

Throws:

SecurityException

renameTo

public abstract boolean renameTo(Resource dest)
                          throws SecurityException

Rename the given resource

Throws:

SecurityException

list

public abstract String[] list()

Returns a list of resource names contained in the given resource The resource names are not URL encoded.

addPath

public abstract Resource addPath(String path)
                          throws IOException,
                                 MalformedURLException

Returns the resource contained inside the current resource with the given name.

Parameters:

path - The path segment to add, which is not encoded

Throws:

IOException

MalformedURLException

getResource

public Resource getResource(String path)

Get a resource from within this resource.

This method is essentially an alias for addPath(String), but without checked exceptions. This method satisfied the ResourceFactory interface.

Specified by:

getResource in interface ResourceFactory

Parameters:

path - The path to the resource

Returns:

The resource or null

See Also:

ResourceFactory.getResource(java.lang.String)

encode

public String encode(String uri)

Deprecated.

getAssociate

public Object getAssociate()

setAssociate

public void setAssociate(Object o)

getAlias

public URI getAlias()

Returns:

The canonical Alias of this resource or null if none.

getListHTML

public String getListHTML(String base,
                 boolean parent)
                   throws IOException

Get the resource list as a HTML directory listing.

Parameters:

base - The base URL

parent - True if the parent directory should be included

Returns:

String of HTML

Throws:

IOException

writeTo

public void writeTo(OutputStream out,
           long start,
           long count)
             throws IOException

Parameters:

out -

start - First byte to write

count - Bytes to write or -1 for all of them.

Throws:

IOException

copyTo

public void copyTo(File destination)
            throws IOException

Throws:

IOException

getWeakETag

public String getWeakETag()

getAllResources

public Collection<Resource> getAllResources()

toURL

public static URL toURL(File file)
                 throws MalformedURLException

Generate a properly encoded URL from a File instance.

Parameters:

file - Target file.

Returns:

URL of the target file.

Throws:

MalformedURLException