org.apache.tools.ant.taskdefs.optional.extension

Class Extension


public final class Extension
extends java.lang.Object

Utility class that represents either an available "Optional Package" (formerly known as "Standard Extension") as described in the manifest of a JAR file, or the requirement for such an optional package.

For more information about optional packages, see the document Optional Package Versioning in the documentation bundle for your Java2 Standard Edition package, in file guide/extensions/versioning.html.

Field Summary

static Compatibility
COMPATIBLE
Enum indicating that extension is compatible with other extension.
static Attributes.Name
EXTENSION_LIST
Manifest Attribute Name object for EXTENSION_LIST.
static Attributes.Name
EXTENSION_NAME
Manifest Attribute Name object for EXTENSION_NAME.
static Attributes.Name
IMPLEMENTATION_URL
Manifest Attribute Name object for IMPLEMENTATION_URL.
static Attributes.Name
IMPLEMENTATION_VENDOR
Manifest Attribute Name object for IMPLEMENTATION_VENDOR.
static Attributes.Name
IMPLEMENTATION_VENDOR_ID
Manifest Attribute Name object for IMPLEMENTATION_VENDOR_ID.
static Attributes.Name
IMPLEMENTATION_VERSION
Manifest Attribute Name object for IMPLEMENTATION_VERSION.
static Compatibility
INCOMPATIBLE
Enum indicating that extension is incompatible with other extension in ways other than other enums indicate).
static Attributes.Name
OPTIONAL_EXTENSION_LIST
Name object for Optional-Extension-List manifest attribute used for declaring optional dependencies on installed extensions.
static Compatibility
REQUIRE_IMPLEMENTATION_UPGRADE
Enum indicating that extension requires an upgrade of implementation to be compatible with other extension.
static Compatibility
REQUIRE_SPECIFICATION_UPGRADE
Enum indicating that extension requires an upgrade of specification to be compatible with other extension.
static Compatibility
REQUIRE_VENDOR_SWITCH
Enum indicating that extension requires a vendor switch to be compatible with other extension.
static Attributes.Name
SPECIFICATION_VENDOR
Manifest Attribute Name object for SPECIFICATION_VENDOR.
static Attributes.Name
SPECIFICATION_VERSION
Manifest Attribute Name object for SPECIFICATION_VERSION.

Constructor Summary

Extension(String extensionName, String specificationVersion, String specificationVendor, String implementationVersion, String implementationVendor, String implementationVendorId, String implementationURL)
The constructor to create Extension object.

Method Summary

static void
addExtension(Extension extension, Attributes attributes)
Add Extension to the specified manifest Attributes.
static void
addExtension(Extension extension, String prefix, Attributes attributes)
Add Extension to the specified manifest Attributes.
static Extension[]
getAvailable(Manifest manifest)
Return an array of Extension objects representing optional packages that are available in the JAR file associated with the specified Manifest.
Compatibility
getCompatibilityWith(Extension required)
Return a Compatibility enum indicating the relationship of this Extension with the specified Extension.
String
getExtensionName()
Get the name of the extension.
String
getImplementationURL()
Get the url of the extensions implementation.
String
getImplementationVendor()
Get the vendor of the extensions implementation.
String
getImplementationVendorID()
Get the vendorID of the extensions implementation.
DeweyDecimal
getImplementationVersion()
Get the version of the extensions implementation.
static Extension[]
getOptions(Manifest manifest)
Return the set of Extension objects representing "Optional Packages" that the application declares they will use if present.
static Extension[]
getRequired(Manifest manifest)
Return the set of Extension objects representing optional packages that are required by the application contained in the JAR file associated with the specified Manifest.
String
getSpecificationVendor()
Get the vendor of the extensions specification.
DeweyDecimal
getSpecificationVersion()
Get the version of the extensions specification.
boolean
isCompatibleWith(Extension required)
Return true if the specified Extension (which represents an optional package required by an application) is satisfied by this Extension (which represents an optional package that is already installed.
String
toString()
Return a String representation of this object.

Field Details

COMPATIBLE

public static final Compatibility COMPATIBLE
Enum indicating that extension is compatible with other extension.

EXTENSION_LIST

public static final Attributes.Name EXTENSION_LIST
Manifest Attribute Name object for EXTENSION_LIST.

EXTENSION_NAME

public static final Attributes.Name EXTENSION_NAME
Manifest Attribute Name object for EXTENSION_NAME.

IMPLEMENTATION_URL

public static final Attributes.Name IMPLEMENTATION_URL
Manifest Attribute Name object for IMPLEMENTATION_URL.

IMPLEMENTATION_VENDOR

public static final Attributes.Name IMPLEMENTATION_VENDOR
Manifest Attribute Name object for IMPLEMENTATION_VENDOR.

IMPLEMENTATION_VENDOR_ID

public static final Attributes.Name IMPLEMENTATION_VENDOR_ID
Manifest Attribute Name object for IMPLEMENTATION_VENDOR_ID.

IMPLEMENTATION_VERSION

public static final Attributes.Name IMPLEMENTATION_VERSION
Manifest Attribute Name object for IMPLEMENTATION_VERSION.

INCOMPATIBLE

public static final Compatibility INCOMPATIBLE
Enum indicating that extension is incompatible with other extension in ways other than other enums indicate). For example the other extension may have a different ID.

OPTIONAL_EXTENSION_LIST

public static final Attributes.Name OPTIONAL_EXTENSION_LIST
Name object for Optional-Extension-List manifest attribute used for declaring optional dependencies on installed extensions. Note that the dependencies declared by this method are not required for the library to operate but if present will be used. It is NOT part of the official "Optional Package" specification.

REQUIRE_IMPLEMENTATION_UPGRADE

public static final Compatibility REQUIRE_IMPLEMENTATION_UPGRADE
Enum indicating that extension requires an upgrade of implementation to be compatible with other extension.

REQUIRE_SPECIFICATION_UPGRADE

public static final Compatibility REQUIRE_SPECIFICATION_UPGRADE
Enum indicating that extension requires an upgrade of specification to be compatible with other extension.

REQUIRE_VENDOR_SWITCH

public static final Compatibility REQUIRE_VENDOR_SWITCH
Enum indicating that extension requires a vendor switch to be compatible with other extension.

SPECIFICATION_VENDOR

public static final Attributes.Name SPECIFICATION_VENDOR
Manifest Attribute Name object for SPECIFICATION_VENDOR.

SPECIFICATION_VERSION

public static final Attributes.Name SPECIFICATION_VERSION
Manifest Attribute Name object for SPECIFICATION_VERSION.

Constructor Details

Extension

public Extension(String extensionName,
                 String specificationVersion,
                 String specificationVendor,
                 String implementationVersion,
                 String implementationVendor,
                 String implementationVendorId,
                 String implementationURL)
The constructor to create Extension object. Note that every component is allowed to be specified but only the extensionName is mandatory.
Parameters:
extensionName - the name of extension.
specificationVersion - the specification Version of extension.
specificationVendor - the specification Vendor of extension.
implementationVersion - the implementation Version of extension.
implementationVendor - the implementation Vendor of extension.
implementationVendorId - the implementation VendorId of extension.
implementationURL - the implementation URL of extension.

Method Details

addExtension

public static void addExtension(Extension extension,
                                Attributes attributes)
Add Extension to the specified manifest Attributes.
Parameters:
extension - the extension
attributes - the attributes of manifest to add to

addExtension

public static void addExtension(Extension extension,
                                String prefix,
                                Attributes attributes)
Add Extension to the specified manifest Attributes. Use the specified prefix so that dependencies can added with a prefix such as "java3d-" etc.
Parameters:
extension - the extension
prefix - the name to prefix to extension
attributes - the attributes of manifest to add to

getAvailable

public static Extension[] getAvailable(Manifest manifest)
Return an array of Extension objects representing optional packages that are available in the JAR file associated with the specified Manifest. If there are no such optional packages, a zero-length array is returned.
Parameters:
manifest - Manifest to be parsed
Returns:
the "available" extensions in specified manifest

getCompatibilityWith

public Compatibility getCompatibilityWith(Extension required)
Return a Compatibility enum indicating the relationship of this Extension with the specified Extension.
Parameters:
required - Description of the required optional package
Returns:
the enum indicating the compatibility (or lack thereof) of specifed extension

getExtensionName

public String getExtensionName()
Get the name of the extension.
Returns:
the name of the extension

getImplementationURL

public String getImplementationURL()
Get the url of the extensions implementation.
Returns:
the url of the extensions implementation.

getImplementationVendor

public String getImplementationVendor()
Get the vendor of the extensions implementation.
Returns:
the vendor of the extensions implementation.

getImplementationVendorID

public String getImplementationVendorID()
Get the vendorID of the extensions implementation.
Returns:
the vendorID of the extensions implementation.

getImplementationVersion

public DeweyDecimal getImplementationVersion()
Get the version of the extensions implementation.
Returns:
the version of the extensions implementation.

getOptions

public static Extension[] getOptions(Manifest manifest)
Return the set of Extension objects representing "Optional Packages" that the application declares they will use if present. If there are no such optional packages, a zero-length list is returned.
Parameters:
manifest - Manifest to be parsed
Returns:
the optional dependencies that are specified in manifest

getRequired

public static Extension[] getRequired(Manifest manifest)
Return the set of Extension objects representing optional packages that are required by the application contained in the JAR file associated with the specified Manifest. If there are no such optional packages, a zero-length list is returned.
Parameters:
manifest - Manifest to be parsed
Returns:
the dependencies that are specified in manifes

getSpecificationVendor

public String getSpecificationVendor()
Get the vendor of the extensions specification.
Returns:
the vendor of the extensions specification.

getSpecificationVersion

public DeweyDecimal getSpecificationVersion()
Get the version of the extensions specification.
Returns:
the version of the extensions specification.

isCompatibleWith

public boolean isCompatibleWith(Extension required)
Return true if the specified Extension (which represents an optional package required by an application) is satisfied by this Extension (which represents an optional package that is already installed. Otherwise, return false.
Parameters:
required - Description of the required optional package
Returns:
true if the specified extension is compatible with this extension

toString

public String toString()
Return a String representation of this object.
Returns:
string representation of object.

Copyright B) 2000-2008 Apache Software Foundation. All Rights Reserved.