org.osgi.framework.wiring

## Interface BundleWiring

All Superinterfaces:
  BundleReference, Wiring

All Known Implementing Classes:
  BundleWiringImpl

    @ProviderType
    public interface BundleWiring
    extends BundleReference, Wiring

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`.

Author:
  $Id: ddad9df28bbd85405057e1f1237f404f83ac8758 $

### Field Summary

Fields
`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

All Methods Instance Methods Abstract Methods
`List<URL>` `findEntries(String path, String filePattern, int options)` Returns entries in this bundle wiring's `bundle revision` and its attached fragment revisions.
`List<BundleCapability>` `getCapabilities(String namespace)` Returns the capabilities provided by this bundle wiring.
`ClassLoader` `getClassLoader()` Returns the class loader for this bundle wiring.
`List<Wire>` `getProvidedResourceWires(String namespace)` Returns the `Wire`s to the provided `capabilities` of this wiring.
`List<BundleWire>` `getProvidedWires(String namespace)` Returns the `BundleWire`s to the provided `capabilities` of this bundle wiring.
`List<Wire>` `getRequiredResourceWires(String namespace)` Returns the `Wire`s to the `requirements` in use by this wiring.
`List<BundleWire>` `getRequiredWires(String namespace)` Returns the `BundleWire`s to the `requirements` in use by this bundle wiring.
`List<BundleRequirement>` `getRequirements(String namespace)` Returns the requirements of this bundle wiring.
`BundleRevision` `getResource()` Returns the resource associated with this wiring.
`List<Capability>` `getResourceCapabilities(String namespace)` Returns the capabilities provided by this wiring.
`List<Requirement>` `getResourceRequirements(String namespace)` Returns the requirements of this 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.
`Collection<String>` `listResources(String path, 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

    List<BundleCapability> getCapabilities(String namespace)

Returns the capabilities provided by this bundle wiring.

Only capabilities considered by the resolver are returned. For example, capabilities with `effective` directive not equal to `resolve` are not returned.

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 both exported and imported, only one is selected and the other is discarded.

A bundle wiring for a fragment revision with a symbolic name must provide exactly one `identity` capability.

† The `identity` capability provided by attached fragment revisions must not be included in the capabilities of the host bundle wiring.

Parameters:
  `namespace` - The namespace of the capabilities to return or `null` to return the capabilities from all namespaces.
Returns:
  A list containing a snapshot of the `BundleCapability`s, or an empty list if this bundle wiring provides no capabilities in the specified namespace. If this bundle wiring is not `in use`, `null` will be returned. For a given namespace, the list contains the capabilities 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 namespaces.

#### getRequirements

    List<BundleRequirement> getRequirements(String namespace)

Returns the requirements of this bundle wiring.

Only requirements considered by the resolver are returned. For example, requirements with `effective` directive not equal to `resolve` are not returned.

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 both exported and imported, only one is selected and the other is discarded.

Parameters:
  `namespace` - The namespace of the requirements to return or `null` to return the requirements from all namespaces.
Returns:
  A list containing a snapshot of the `BundleRequirement`s, or an empty list if this bundle wiring uses no requirements in the specified namespace. If this bundle wiring is not `in use`, `null` will be returned. For a given namespace, the list contains the requirements 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 namespaces.

#### getProvidedWires

    List<BundleWire> getProvidedWires(String namespace)

Returns the `BundleWire`s to the provided `capabilities` of this bundle wiring.

Parameters:
  `namespace` - The namespace of the capabilities for which to return wires or `null` to return the wires for the capabilities in all namespaces.
Returns:
  A list containing a snapshot of the `BundleWire`s for the `capabilities` of this bundle wiring, or an empty list if this bundle wiring has no capabilities in the specified namespace. If this bundle wiring is not `in use`, `null` will be returned. For a given namespace, 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 namespaces.

#### getRequiredWires

    List<BundleWire> getRequiredWires(String namespace)

Returns the `BundleWire`s to the `requirements` in use by this bundle wiring.

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

Parameters:
  `namespace` - The namespace of the requirements for which to return wires or `null` to return the wires for the requirements in all namespaces.
Returns:
  A list containing a snapshot of the `BundleWire`s for the `requirements` of this bundle wiring, or an empty list if this bundle wiring has no requirements in the specified namespace. If this bundle wiring is not `in use`, `null` will be returned. For a given namespace, 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 followed by dynamically established wires, if any, in the order they were established. There is no ordering defined between requirements in different namespaces.

#### 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

    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:
  `SecurityException` - If the caller does not have the appropriate `RuntimePermission("getClassLoader")`, and the Java Runtime Environment supports permissions.

#### findEntries

    List<URL> findEntries(String path,
                          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 namespace 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.

URLs for directory entries must have their path end with "/".

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

    Collection<String> listResources(String path,
                                     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.

- Only the resource names for resources in bundle wirings will be returned. The names of resources visible to a bundle wiring's parent class loader, such as the bootstrap class loader, must not be included in the result.
- Only established wires will be examined for resources. This method must not cause new wires for dynamic imports to be established.

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.

#### getResourceCapabilities

    List<Capability> getResourceCapabilities(String namespace)

Returns the capabilities provided by this wiring.

Only capabilities considered by the resolver are returned. For example, capabilities with `effective` directive not equal to `resolve` are not returned.

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

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

A wiring for a fragment resource with a symbolic name must provide exactly one `osgi.identity` capability.

† The `osgi.identity` capability provided by attached fragment resource must not be included in the capabilities of the host wiring.

This method returns the same value as `getCapabilities(String)`.

Specified by:
  `getResourceCapabilities` in interface `Wiring`
Parameters:
  `namespace` - The namespace of the capabilities to return or `null` to return the capabilities from all namespaces.
Returns:
  A list containing a snapshot of the `Capability`s, or an empty list if this wiring provides no capabilities in the specified namespace. For a given namespace, the list contains the capabilities in the order the capabilities were specified in the manifests of the `resource` and the attached fragment resources† of this wiring. There is no ordering defined between capabilities in different namespaces.
Since:
  1.1

#### getResourceRequirements

    List<Requirement> getResourceRequirements(String namespace)

Returns the requirements of this wiring.

Only requirements considered by the resolver are returned. For example, requirements with `effective` directive not equal to `resolve` are not returned.

A wiring for a non-fragment resource has a subset of the declared requirements from the resource and all attached fragment resources. 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.

This method returns the same value as `getRequirements(String)`.

Specified by:
  `getResourceRequirements` in interface `Wiring`
Parameters:
  `namespace` - The namespace of the requirements to return or `null` to return the requirements from all namespaces.
Returns:
  A list containing a snapshot of the `Requirement`s, or an empty list if this wiring uses no requirements in the specified namespace. For a given namespace, the list contains the requirements in the order the requirements were specified in the manifests of the `resource` and the attached fragment resources of this wiring. There is no ordering defined between requirements in different namespaces.
Since:
  1.1

#### getProvidedResourceWires

    List<Wire> getProvidedResourceWires(String namespace)

Returns the `Wire`s to the provided `capabilities` of this wiring.

This method returns the same value as `getProvidedWires(String)`.

Specified by:
  `getProvidedResourceWires` in interface `Wiring`
Parameters:
  `namespace` - The namespace of the capabilities for which to return wires or `null` to return the wires for the capabilities in all namespaces.
Returns:
  A list containing a snapshot of the `Wire`s for the `capabilities` of this wiring, or an empty list if this wiring has no capabilities in the specified namespace. For a given namespace, the list contains the wires in the order the capabilities were specified in the manifests of the `resource` and the attached fragment resources of this wiring. There is no ordering defined between capabilities in different namespaces.
Since:
  1.1

#### getRequiredResourceWires

    List<Wire> getRequiredResourceWires(String namespace)

Returns the `Wire`s to the `requirements` in use by this wiring.

This method returns the same value as `getRequiredWires(String)`.

Specified by:
  `getRequiredResourceWires` in interface `Wiring`
Parameters:
  `namespace` - The namespace of the requirements for which to return wires or `null` to return the wires for the requirements in all namespaces.
Returns:
  A list containing a snapshot of the `Wire`s for the `requirements` of this wiring, or an empty list if this wiring has no requirements in the specified namespace. For a given namespace, the list contains the wires in the order the requirements were specified in the manifests of the `resource` and the attached fragment resources of this wiring. There is no ordering defined between requirements in different namespaces.
Since:
  1.1

#### getResource

    BundleRevision getResource()

Returns the resource associated with this wiring.

This method returns the same value as `getRevision()`.

Specified by:
  `getResource` in interface `Wiring`
Returns:
  The resource associated with this wiring.
Since:
  1.1