org.eclipse.gemini.blueprint.io

Class OsgiBundleResource

java.lang.Object

org.springframework.core.io.AbstractResource

org.eclipse.gemini.blueprint.io.OsgiBundleResource

All Implemented Interfaces:

org.springframework.core.io.ContextResource, org.springframework.core.io.InputStreamSource, org.springframework.core.io.Resource

public class OsgiBundleResource
extends org.springframework.core.io.AbstractResource
implements org.springframework.core.io.ContextResource

Resource implementation for OSGi environments.

Lazy evaluation of the resource will be used. This implementation allows resource location inside:

• bundle space - if osgibundle:/ BUNDLE_URL_PREFIX prefix is being used or none is specified. This space cotnains the bundle jar and its attached fragments.
• bundle jar - if osgibundlejar:/ BUNDLE_JAR_URL_PREFIX is specified. This space contains just the bundle jar.
• class space - if ResourceUtils.CLASSPATH_URL_PREFIX is encountered. This space contains the bundle classpath, namely the bundle jar, its attached fragments and imported packages.

For more explanations on resource locations in OSGi, please see the Access to Resources chapter from the OSGi spec.

OSGi framework specific prefixes (such as bundleentry: and bundleresource:under Equinox, bundle: under Knopflefish and Felix, etc..) are supported. Resources outside the OSGi space (file:, http:, etc..) are supported as well as the path is being resolved to an URL.

If no prefix is specified, the bundle space will be used for locating a resource.

Note: When the bundle space (bundle jar and its attached fragments) is being searched, multiple URLs can be found but this implementation will return only the first one. Consider using OsgiBundleResourcePatternResolver to retrieve all entries.

Field Summary

Fields

Modifier and Type	Field and Description
private static java.lang.String	ABSOLUTE_PATH_PREFIX
private org.osgi.framework.Bundle	bundle
static java.lang.String	BUNDLE_JAR_URL_PREFIX Prefix for searching only the bundle raw jar.
static java.lang.String	BUNDLE_URL_PREFIX Prefix for searching inside the owning bundle space.
private java.lang.String	path
private java.lang.String	pathWithoutPrefix
private static char	PREFIX_SEPARATOR
private int	searchType

Constructor Summary

Constructors

Constructor and Description
OsgiBundleResource(org.osgi.framework.Bundle bundle, java.lang.String path) Constructs a new OsgiBundleResource instance.

Method Summary

Modifier and Type	Method and Description
org.springframework.core.io.Resource	createRelative(java.lang.String relativePath) Returns a resource relative to this resource.
boolean	equals(java.lang.Object obj) This implementation compares the underlying bundle and path locations.
boolean	exists() Return whether this resource actually exists in physical form.
(package private) org.springframework.core.io.ContextResource[]	getAllUrlsFromBundleSpace(java.lang.String location) Used internally to get all the URLs matching a certain location.
(package private) org.osgi.framework.Bundle	getBundle() Returns the bundle for this resource.
java.lang.String	getDescription() This implementation returns a description that includes the bundle location.
java.io.File	getFile() Returns a File handle for this resource.
java.lang.String	getFilename() Returns the filename of this resources.
java.io.InputStream	getInputStream() Returns an InputStream to this resource.
(package private) java.lang.String	getPath() Returns the path for this resource.
java.lang.String	getPathWithinContext()
(package private) java.net.URL	getResourceFromBundleClasspath(java.lang.String bundlePath) Resolves a resource from the bundle's classpath.
(package private) java.net.URL	getResourceFromBundleJar(java.lang.String bundlePath) Resolves a resource from the *bundle jar* only.
(package private) org.springframework.core.io.ContextResource	getResourceFromBundleSpace(java.lang.String bundlePath) Resolves a resource from *the bundle space* only.
(package private) int	getSearchType()
java.net.URL	getURL() Locates the resource in the underlying bundle based on the prefix, if it exists.
int	hashCode() This implementation returns the hash code of the underlying class path location.
(package private) boolean	isRelativePath(java.lang.String locationPath) Determine if the given path is relative or absolute.
long	lastModified()

Methods inherited from class org.springframework.core.io.AbstractResource

contentLength, getFileForLastModifiedCheck, getURI, isOpen, isReadable, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.springframework.core.io.Resource

contentLength, getURI, isOpen, isReadable

Field Detail

BUNDLE_URL_PREFIX

public static final java.lang.String BUNDLE_URL_PREFIX

Prefix for searching inside the owning bundle space. This translates to searching the bundle and its attached fragments. If no prefix is specified, this one will be used.

See Also:

Constant Field Values

BUNDLE_JAR_URL_PREFIX

public static final java.lang.String BUNDLE_JAR_URL_PREFIX

Prefix for searching only the bundle raw jar. Will ignore attached fragments. Not used at the moment.

See Also:

Constant Field Values

PREFIX_SEPARATOR

private static final char PREFIX_SEPARATOR

See Also:

Constant Field Values

ABSOLUTE_PATH_PREFIX

private static final java.lang.String ABSOLUTE_PATH_PREFIX

See Also:

Constant Field Values

bundle

private final org.osgi.framework.Bundle bundle

path

private final java.lang.String path

pathWithoutPrefix

private final java.lang.String pathWithoutPrefix

searchType

private int searchType

Constructor Detail

OsgiBundleResource

public OsgiBundleResource(org.osgi.framework.Bundle bundle,
                          java.lang.String path)

Constructs a new OsgiBundleResource instance.

Parameters:

bundle - OSGi bundle used by this resource

path - resource path inside the bundle.

Method Detail

getPath

final java.lang.String getPath()

Returns the path for this resource.

Returns:

this resource path

getBundle

final org.osgi.framework.Bundle getBundle()

Returns the bundle for this resource.

Returns:

the resource bundle

getInputStream

public java.io.InputStream getInputStream()
                                   throws java.io.IOException

Returns an InputStream to this resource. This implementation opens an InputStream for the given URL. It sets the UseCaches flag to false, mainly to avoid jar file locking on Windows.

Specified by:

getInputStream in interface org.springframework.core.io.InputStreamSource

Returns:

input stream to the underlying resource

Throws:

java.io.IOException - if the stream could not be opened

See Also:

URL.openConnection(), URLConnection.setUseCaches(boolean), URLConnection.getInputStream()

getURL

public java.net.URL getURL()
                    throws java.io.IOException

Locates the resource in the underlying bundle based on the prefix, if it exists. Note that the location happens per call since due to the dynamic nature of OSGi, the classpath of the bundle (among others) can change during a bundle lifecycle (depending on its imports).

Specified by:

getURL in interface org.springframework.core.io.Resource

Overrides:

getURL in class org.springframework.core.io.AbstractResource

Returns:

URL to this resource

Throws:

java.io.IOException - if the resource cannot be resolved as URL, i.e. if the resource is not available as descriptor

See Also:

Bundle.getEntry(String), Bundle.getResource(String)

getResourceFromBundleSpace

org.springframework.core.io.ContextResource getResourceFromBundleSpace(java.lang.String bundlePath)
                                                                throws java.io.IOException

Resolves a resource from *the bundle space* only. Only the bundle and its attached fragments are searched for the given resource. Note that this method returns only the first URL found, discarding the rest. To retrieve the entire set, consider using OsgiBundleResourcePatternResolver.

Parameters:

bundlePath - the path to resolve

Returns:

a URL to the returned resource or null if none is found

Throws:

java.io.IOException

See Also:

org.osgi.framework.Bundle#findEntries(String, String, boolean)}

getResourceFromBundleJar

java.net.URL getResourceFromBundleJar(java.lang.String bundlePath)
                               throws java.io.IOException

Resolves a resource from the *bundle jar* only. Only the bundle jar is searched (its attached fragments are ignored).

Parameters:

bundlePath - the path to resolve

Returns:

URL to the specified path or null if none is found

Throws:

java.io.IOException

See Also:

Bundle#getEntry(String)}

getResourceFromBundleClasspath

java.net.URL getResourceFromBundleClasspath(java.lang.String bundlePath)

Resolves a resource from the bundle's classpath. This will find resources in this bundle and also in imported packages from other bundles.

Parameters:

bundlePath -

Returns:

a URL to the returned resource or null if none is found

See Also:

Bundle.getResource(String)

isRelativePath

boolean isRelativePath(java.lang.String locationPath)

Determine if the given path is relative or absolute.

Parameters:

locationPath -

Returns:

createRelative

public org.springframework.core.io.Resource createRelative(java.lang.String relativePath)

Returns a resource relative to this resource. This implementation creates an OsgiBundleResource, applying the given path relative to the path of the underlying resource of this descriptor.

Specified by:

createRelative in interface org.springframework.core.io.Resource

Overrides:

createRelative in class org.springframework.core.io.AbstractResource

Parameters:

relativePath - the relative path (relative to this resource)

Returns:

the resource handle for the relative resource

Throws:

java.io.IOException - if the relative resource cannot be determined

See Also:

StringUtils.applyRelativePath(String, String)

getFilename

public java.lang.String getFilename()

Returns the filename of this resources. This implementation returns the name of the file that this bundle path resource refers to.

Specified by:

getFilename in interface org.springframework.core.io.Resource

Overrides:

getFilename in class org.springframework.core.io.AbstractResource

Returns:

resource filename

See Also:

StringUtils.getFilename(String)

getFile

public java.io.File getFile()
                     throws java.io.IOException

Returns a File handle for this resource. This method does a best-effort attempt to locate the bundle resource on the file system. It is strongly recommended to use getInputStream() method instead which works no matter if the bundles are saved (in exploded form or not) on the file system.

Specified by:

getFile in interface org.springframework.core.io.Resource

Overrides:

getFile in class org.springframework.core.io.AbstractResource

Returns:

File handle to this resource

Throws:

java.io.IOException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

getDescription

public java.lang.String getDescription()

This implementation returns a description that includes the bundle location.

Specified by:

getDescription in interface org.springframework.core.io.Resource

equals

public boolean equals(java.lang.Object obj)

This implementation compares the underlying bundle and path locations.

Overrides:

equals in class org.springframework.core.io.AbstractResource

hashCode

public int hashCode()

This implementation returns the hash code of the underlying class path location.

Overrides:

hashCode in class org.springframework.core.io.AbstractResource

lastModified

public long lastModified()
                  throws java.io.IOException

Specified by:

lastModified in interface org.springframework.core.io.Resource

Overrides:

lastModified in class org.springframework.core.io.AbstractResource

Throws:

java.io.IOException

getSearchType

int getSearchType()

Returns:

Returns the searchType.

getAllUrlsFromBundleSpace

org.springframework.core.io.ContextResource[] getAllUrlsFromBundleSpace(java.lang.String location)
                                                                 throws java.io.IOException

Used internally to get all the URLs matching a certain location. The method is required to extract the folder from the given location as well the file.

Parameters:

location - location to look for

Returns:

an array of URLs

Throws:

java.io.IOException

getPathWithinContext

public java.lang.String getPathWithinContext()

Specified by:

getPathWithinContext in interface org.springframework.core.io.ContextResource

exists

public boolean exists()

Return whether this resource actually exists in physical form.

This method performs a definitive existence check, whereas the existence of a Resource handle only guarantees a valid descriptor handle.

The existence check is done by opening an InputStream to the underlying resource (overriding the default implementation which checks first for the presence of a File).

Specified by:

exists in interface org.springframework.core.io.Resource

Overrides:

exists in class org.springframework.core.io.AbstractResource