OSGi™ Service Platform
Core Specification

Release 4 Version 4.3

org.osgi.framework.wiring
Interface BundleWiring

All Superinterfaces:
BundleReference

public interface BundleWiring
extends BundleReference

A wiring for a bundle. Each time a bundle is resolved, a new bundle wiring for the bundle is created. A bundle wiring is associated with a bundle revision and represents the dependencies with other bundle wirings.

The bundle wiring for a bundle is the current bundle wiring if it is the most recent bundle wiring for the current bundle revision. A bundle wiring is in use if it is the current bundle wiring or if some other in use bundle wiring is dependent upon it. For example, another bundle wiring is wired to a capability provided by the bundle wiring. An in use bundle wiring for a non-fragment bundle has a class loader. All bundles with non-current, in use bundle wirings are considered removal pending. Once a bundle wiring is no longer in use, it is considered stale and is discarded by the framework.

The current bundle wiring for a bundle can be obtained by calling bundle.adapt(BundleWiring.class). A bundle in the INSTALLED or UNINSTALLED state does not have a current wiring, adapting such a bundle returns null.

ThreadSafe
Consumers of this API must not implement this interface

Field Summary
static int FINDENTRIES_RECURSE
          The find entries operation must recurse into subdirectories.
static int LISTRESOURCES_LOCAL
          The list resource names operation must limit the result to the names of matching resources contained in this bundle wiring's bundle revision and its attached fragment revisions.
static int LISTRESOURCES_RECURSE
          The list resource names operation must recurse into subdirectories.
 
Method Summary
 java.util.List<java.net.URL> findEntries(java.lang.String path, java.lang.String filePattern, int options)
          Returns entries in this bundle wiring's bundle revision and its attached fragment revisions.
 java.util.List<BundleCapability> getCapabilities(java.lang.String namespace)
          Returns the capabilities provided by this bundle wiring.
 java.lang.ClassLoader getClassLoader()
          Returns the class loader for this bundle wiring.
 java.util.List<BundleWire> getProvidedWires(java.lang.String namespace)
          Returns the BundleWires to the provided capabilities of this bundle wiring.
 java.util.List<BundleWire> getRequiredWires(java.lang.String namespace)
          Returns the BundleWires to the requirements in use by this bundle wiring.
 java.util.List<BundleRequirement> getRequirements(java.lang.String namespace)
          Returns the requirements of this bundle wiring.
 BundleRevision getRevision()
          Returns the bundle revision for the bundle in this bundle wiring.
 boolean isCurrent()
          Returns true if this bundle wiring is the current bundle wiring.
 boolean isInUse()
          Returns true if this bundle wiring is in use.
 java.util.Collection<java.lang.String> listResources(java.lang.String path, java.lang.String filePattern, int options)
          Returns the names of resources visible to this bundle wiring's class loader.
 
Methods inherited from interface org.osgi.framework.BundleReference
getBundle
 

Field Detail

FINDENTRIES_RECURSE

static final int FINDENTRIES_RECURSE
The find entries operation must recurse into subdirectories.

This bit may be set when calling findEntries(String, String, int) to specify the result must include the matching entries from the specified path and its subdirectories. If this bit is not set, then the result must only include matching entries from the specified path.

See Also:
findEntries(String, String, int), Constant Field Values

LISTRESOURCES_RECURSE

static final int LISTRESOURCES_RECURSE
The list resource names operation must recurse into subdirectories.

This bit may be set when calling listResources(String, String, int) to specify the result must include the names of matching resources from the specified path and its subdirectories. If this bit is not set, then the result must only include names of matching resources from the specified path.

See Also:
listResources(String, String, int), Constant Field Values

LISTRESOURCES_LOCAL

static final int LISTRESOURCES_LOCAL
The list resource names operation must limit the result to the names of matching resources contained in this bundle wiring's bundle revision and its attached fragment revisions. The result must not include resource names for resources in package names which are imported by this wiring.

This bit may be set when calling listResources(String, String, int) to specify the result must only include the names of matching resources contained in this bundle wiring's bundle revision and its attached fragment revisions. If this bit is not set, then the result must include the names of matching resources reachable from this bundle wiring's class loader which may include the names of matching resources contained in imported packages and required bundles.

See Also:
listResources(String, String, int), Constant Field Values
Method Detail

isCurrent

boolean isCurrent()
Returns true if this bundle wiring is the current bundle wiring. The bundle wiring for a bundle is the current bundle wiring if it is the most recent bundle wiring for the current bundle revision. All bundles with non-current, in use bundle wirings are considered removal pending.

Returns:
true if this bundle wiring is the current bundle wiring; false otherwise.

isInUse

boolean isInUse()
Returns true if this bundle wiring is in use. A bundle wiring is in use if it is the current wiring or if some other in use bundle wiring is dependent upon it. Once a bundle wiring is no longer in use, it is considered stale and is discarded by the framework.

Returns:
true if this bundle wiring is in use; false otherwise.

getCapabilities

java.util.List<BundleCapability> getCapabilities(java.lang.String namespace)
Returns the capabilities provided by this bundle wiring.

A capability may not be required by any bundle wiring and thus there may be no wires for the capability.

A bundle wiring for a non-fragment revision provides a subset of the declared capabilities from the bundle revision and all attached fragment revisions. Not all declared capabilities may be provided since some may be discarded. For example, if a package is declared to be exported and import, only one is selected and the other is discarded.

Parameters:
namespace - The name space of the capabilities to return or null to return the capabilities from all name spaces.
Returns:
A list containing a snapshot of the BundleCapabilitys, or an empty list if this bundle wiring provides no capabilities in the specified name space. If this bundle wiring is not in use, null will be returned. For a given name space, the list contains the wires in the order the capabilities were specified in the manifests of the bundle revision and the attached fragments of this bundle wiring. There is no ordering defined between capabilities in different name spaces.

getRequirements

java.util.List<BundleRequirement> getRequirements(java.lang.String namespace)
Returns the requirements of this bundle wiring.

A bundle wiring for a non-fragment revision has a subset of the declared requirements from the bundle revision and all attached fragment revisions. Not all declared requirements may be present since some may be discarded. For example, if a package is declared to be optionally imported and is not actually imported, the requirement must be discarded.

Parameters:
namespace - The name space of the requirements to return or null to return the requirements from all name spaces.
Returns:
A list containing a snapshot of the BundleRequirements, or an empty list if this bundle wiring uses no requirements in the specified name space. If this bundle wiring is not in use, null will be returned. For a given name space, the list contains the wires in the order the requirements were specified in the manifests of the bundle revision and the attached fragments of this bundle wiring. There is no ordering defined between requirements in different name spaces.

getProvidedWires

java.util.List<BundleWire> getProvidedWires(java.lang.String namespace)
Returns the BundleWires to the provided capabilities of this bundle wiring.

Parameters:
namespace - The name space of the capabilities for which to return wires or null to return the wires for the capabilities in all name spaces.
Returns:
A list containing a snapshot of the BundleWires for the capabilities of this bundle wiring, or an empty list if this bundle wiring has no capabilities in the specified name space. If this bundle wiring is not in use, null will be returned. For a given name space, the list contains the wires in the order the capabilities were specified in the manifests of the bundle revision and the attached fragments of this bundle wiring. There is no ordering defined between capabilities in different name spaces.

getRequiredWires

java.util.List<BundleWire> getRequiredWires(java.lang.String namespace)
Returns the BundleWires to the requirements in use by this bundle wiring.

This method may return different results if this bundle wiring adds wires to more requirements. For example, dynamically importing a package will establish a new wire to the dynamically imported package.

Parameters:
namespace - The name space of the requirements for which to return wires or null to return the wires for the requirements in all name spaces.
Returns:
A list containing a snapshot of the BundleWires for the requirements of this bundle wiring, or an empty list if this bundle wiring has no requirements in the specified name space. If this bundle wiring is not in use, null will be returned. For a given name space, the list contains the wires in the order the requirements were specified in the manifests of the bundle revision and the attached fragments of this bundle wiring. There is no ordering defined between requirements in different name spaces.

getRevision

BundleRevision getRevision()
Returns the bundle revision for the bundle in this bundle wiring. Since a bundle update can change the entries in a bundle, different bundle wirings for the same bundle can have different bundle revisions.

The bundle object referenced by the returned BundleRevision may return different information than the returned BundleRevision since the returned BundleRevision may refer to an older revision of the bundle.

Returns:
The bundle revision for this bundle wiring.
See Also:
BundleRevision.getWiring()

getClassLoader

java.lang.ClassLoader getClassLoader()
Returns the class loader for this bundle wiring. Since a bundle refresh creates a new bundle wiring for a bundle, different bundle wirings for the same bundle will have different class loaders.

Returns:
The class loader for this bundle wiring. If this bundle wiring is not in use or this bundle wiring is for a fragment revision, null will be returned.
Throws:
java.lang.SecurityException - If the caller does not have the appropriate RuntimePermission("getClassLoader"), and the Java Runtime Environment supports permissions.

findEntries

java.util.List<java.net.URL> findEntries(java.lang.String path,
                                         java.lang.String filePattern,
                                         int options)
Returns entries in this bundle wiring's bundle revision and its attached fragment revisions. This bundle wiring's class loader is not used to search for entries. Only the contents of this bundle wiring's bundle revision and its attached fragment revisions are searched for the specified entries.

This method takes into account that the "contents" of this bundle wiring can have attached fragments. This "bundle space" is not a name space with unique members; the same entry name can be present multiple times. This method therefore returns a list of URL objects. These URLs can come from different JARs but have the same path name. This method can either return only entries in the specified path or recurse into subdirectories returning entries in the directory tree beginning at the specified path.

Note: Jar and zip files are not required to include directory entries. URLs to directory entries will not be returned if the bundle contents do not contain directory entries.

Parameters:
path - The path name in which to look. The path is always relative to the root of this bundle wiring and may begin with "/". A path value of "/" indicates the root of this bundle wiring.
filePattern - The file name pattern for selecting entries in the specified path. The pattern is only matched against the last element of the entry path. If the entry is a directory then the trailing "/" is not used for pattern matching. Substring matching is supported, as specified in the Filter specification, using the wildcard character ("*"). If null is specified, this is equivalent to "*" and matches all files.
options - The options for listing resource names. See FINDENTRIES_RECURSE. The method must ignore unrecognized options.
Returns:
An unmodifiable list of URL objects for each matching entry, or an empty list if no matching entry could be found, if this bundle wiring is for a fragment revision or if the caller does not have the appropriate AdminPermission[bundle,RESOURCE] and the Java Runtime Environment supports permissions. The list is ordered such that entries from the bundle revision are returned first followed by the entries from attached fragment revisions in attachment order. If this bundle wiring is not in use, null must be returned.
See Also:
Bundle.findEntries(String, String, boolean)

listResources

java.util.Collection<java.lang.String> listResources(java.lang.String path,
                                                     java.lang.String filePattern,
                                                     int options)
Returns the names of resources visible to this bundle wiring's class loader. The returned names can be used to access the resources via this bundle wiring's class loader.

Parameters:
path - The path name in which to look. The path is always relative to the root of this bundle wiring's class loader and may begin with "/". A path value of "/" indicates the root of this bundle wiring's class loader.
filePattern - The file name pattern for selecting resource names in the specified path. The pattern is only matched against the last element of the resource path. If the resource is a directory then the trailing "/" is not used for pattern matching. Substring matching is supported, as specified in the Filter specification, using the wildcard character ("*"). If null is specified, this is equivalent to "*" and matches all files.
options - The options for listing resource names. See LISTRESOURCES_LOCAL and LISTRESOURCES_RECURSE. This method must ignore unrecognized options.
Returns:
An unmodifiable collection of resource names for each matching resource, or an empty collection if no matching resource could be found, if this bundle wiring is for a fragment revision or if the caller does not have the appropriate AdminPermission[bundle,RESOURCE] and the Java Runtime Environment supports permissions. The collection is unordered and must contain no duplicate resource names. If this bundle wiring is not in use, null must be returned.

OSGi™ Service Platform
Core Specification

Release 4 Version 4.3

Copyright © OSGi Alliance (2000, 2012). All Rights Reserved. Licensed under the OSGi Specification License, Version 2.0