java.lang.Object
- org.osgi.resource.Namespace
- - org.osgi.framework.namespace.AbstractWiringNamespace
  - - org.osgi.framework.namespace.HostNamespace

```
public final class HostNamespace
extends AbstractWiringNamespace
```
Host Capability and Requirement Namespace.
This class defines the names for the attributes and directives for this namespace. All unspecified capability attributes are of type String and are used as arbitrary matching attributes for the capability. The values associated with the specified directive and attribute keys are of type String, unless otherwise indicated.
Unless otherwise noted, all directives specified on the Bundle-SymbolicName header are visible in the capability and all directives specified on the Fragment-Host header are visible in the requirement.
- The uses directive must be ignored. A uses directive specified on the Bundle-SymbolicName header must be ignored. A uses directive must not be present in the capability.
- The effective directives must be ignored. This namespace is only effective at resolve time. An effective directive specified on the Bundle-SymbolicName or Fragment-Host headers must be ignored. An effective directive must not be present in a capability or requirement.
- The cardinality directive has limited applicability to this namespace. A cardinality directive specified on the Fragment-Host header must be ignored. All requirements must have the cardinality directive set to multiple.
A non-fragment resource with the osgi.bundle type identity provides zero or one^† host capabilities. A fragment resource with the osgi.fragment type identity must not declare a host capability and must declare exactly one host requirement.
† A resource with no bundle symbolic name must not provide a host capability.

Field Summary

Fields
Modifier and Type	Field	Description
`static java.lang.String`	`CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE`	The capability directive identifying if and when a fragment may attach to a host bundle.
`static java.lang.String`	`CAPABILITY_SINGLETON_DIRECTIVE`	The capability directive identifying if the resource is a singleton.
`static java.lang.String`	`EXTENSION_BOOTCLASSPATH`	Deprecated. As of 1.2.
`static java.lang.String`	`EXTENSION_FRAMEWORK`	The directive value indicating that the extension fragment is to be loaded by the framework's class loader.
`static java.lang.String`	`FRAGMENT_ATTACHMENT_ALWAYS`	The directive value indicating that fragments are allowed to attach to the host bundle at any time (while the host is resolved or during the process of resolving the host bundle).
`static java.lang.String`	`FRAGMENT_ATTACHMENT_NEVER`	The directive value indicating that no fragments are allowed to attach to the host bundle at any time.
`static java.lang.String`	`FRAGMENT_ATTACHMENT_RESOLVETIME`	The directive value indicating that fragments are allowed to attach to the host bundle only during the process of resolving the host bundle.
`static java.lang.String`	`HOST_NAMESPACE`	Namespace name for host capabilities and requirements.
`static java.lang.String`	`REQUIREMENT_EXTENSION_DIRECTIVE`	The requirement directive used to specify the type of the extension fragment.
`static java.lang.String`	`REQUIREMENT_VISIBILITY_DIRECTIVE`	The requirement directive used to specify the visibility type for a requirement.

Fields inherited from class org.osgi.framework.namespace.AbstractWiringNamespace
CAPABILITY_BUNDLE_VERSION_ATTRIBUTE, CAPABILITY_MANDATORY_DIRECTIVE

Fields inherited from class org.osgi.resource.Namespace
CAPABILITY_EFFECTIVE_DIRECTIVE, CAPABILITY_USES_DIRECTIVE, CARDINALITY_MULTIPLE, CARDINALITY_SINGLE, EFFECTIVE_ACTIVE, EFFECTIVE_RESOLVE, REQUIREMENT_CARDINALITY_DIRECTIVE, REQUIREMENT_EFFECTIVE_DIRECTIVE, REQUIREMENT_FILTER_DIRECTIVE, REQUIREMENT_RESOLUTION_DIRECTIVE, RESOLUTION_MANDATORY, RESOLUTION_OPTIONAL

Method Summary
- Methods inherited from class java.lang.Object
  equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - HOST_NAMESPACE
```
public static final java.lang.String HOST_NAMESPACE
```
    Namespace name for host capabilities and requirements.
    Also, the capability attribute used to specify the symbolic name of the host.
    
    See Also:
    
    Constant Field Values
  - CAPABILITY_SINGLETON_DIRECTIVE
```
public static final java.lang.String CAPABILITY_SINGLETON_DIRECTIVE
```
    The capability directive identifying if the resource is a singleton. A String value of "true" indicates the resource is a singleton; any other value or null indicates the resource is not a singleton.
    This directive should be examined using the identity namespace.
    
    See Also:
    
    IdentityNamespace.CAPABILITY_SINGLETON_DIRECTIVE, Constant Field Values
  - CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE
```
public static final java.lang.String CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE
```
    The capability directive identifying if and when a fragment may attach to a host bundle. The default value is always.
    
    See Also:
    
    FRAGMENT_ATTACHMENT_ALWAYS, FRAGMENT_ATTACHMENT_RESOLVETIME, FRAGMENT_ATTACHMENT_NEVER, Constant Field Values
  - FRAGMENT_ATTACHMENT_ALWAYS
```
public static final java.lang.String FRAGMENT_ATTACHMENT_ALWAYS
```
    The directive value indicating that fragments are allowed to attach to the host bundle at any time (while the host is resolved or during the process of resolving the host bundle).
    
    See Also:
    
    CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE, Constant Field Values
  - FRAGMENT_ATTACHMENT_RESOLVETIME
```
public static final java.lang.String FRAGMENT_ATTACHMENT_RESOLVETIME
```
    The directive value indicating that fragments are allowed to attach to the host bundle only during the process of resolving the host bundle.
    
    See Also:
    
    CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE, Constant Field Values
  - FRAGMENT_ATTACHMENT_NEVER
```
public static final java.lang.String FRAGMENT_ATTACHMENT_NEVER
```
    The directive value indicating that no fragments are allowed to attach to the host bundle at any time.
    
    See Also:
    
    CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE, Constant Field Values
  - REQUIREMENT_EXTENSION_DIRECTIVE
```
public static final java.lang.String REQUIREMENT_EXTENSION_DIRECTIVE
```
    The requirement directive used to specify the type of the extension fragment. The default value is framework.
    
    See Also:
    
    EXTENSION_FRAMEWORK, Constant Field Values
  - EXTENSION_FRAMEWORK
```
public static final java.lang.String EXTENSION_FRAMEWORK
```
    The directive value indicating that the extension fragment is to be loaded by the framework's class loader.
    
    See Also:
    
    REQUIREMENT_EXTENSION_DIRECTIVE, Constant Field Values
  - EXTENSION_BOOTCLASSPATH
```
public static final java.lang.String EXTENSION_BOOTCLASSPATH
```
    Deprecated.
    As of 1.2.
    
    The directive value indicating that the extension fragment is to be loaded by the boot class loader.
    
    See Also:
    
    REQUIREMENT_EXTENSION_DIRECTIVE, Constant Field Values
  - REQUIREMENT_VISIBILITY_DIRECTIVE
```
public static final java.lang.String REQUIREMENT_VISIBILITY_DIRECTIVE
```
    The requirement directive used to specify the visibility type for a requirement.
    This directive should be examined using the bundle namespace.
    
    See Also:
    
    BundleNamespace.REQUIREMENT_VISIBILITY_DIRECTIVE, Constant Field Values

Class HostNamespace

Field Summary

Fields inherited from class org.osgi.framework.namespace.AbstractWiringNamespace

Fields inherited from class org.osgi.resource.Namespace

Method Summary

Methods inherited from class java.lang.Object

Field Detail

HOST_NAMESPACE

CAPABILITY_SINGLETON_DIRECTIVE

CAPABILITY_FRAGMENT_ATTACHMENT_DIRECTIVE

FRAGMENT_ATTACHMENT_ALWAYS

FRAGMENT_ATTACHMENT_RESOLVETIME

FRAGMENT_ATTACHMENT_NEVER

REQUIREMENT_EXTENSION_DIRECTIVE

EXTENSION_FRAMEWORK

EXTENSION_BOOTCLASSPATH

REQUIREMENT_VISIBILITY_DIRECTIVE