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

Class Extension

java.lang.Object

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

public final class Extension
extends 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

Fields

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

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method	Description
static void	addExtension(Extension extension, String prefix, Attributes attributes)	Add Extension to the specified manifest Attributes.
static void	addExtension(Extension extension, 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.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

EXTENSION_LIST

public static final Attributes.Name EXTENSION_LIST

Manifest Attribute Name object for EXTENSION_LIST.

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.

See Also:

• Installed extension dependency

EXTENSION_NAME

public static final Attributes.Name EXTENSION_NAME

Manifest Attribute Name object for EXTENSION_NAME.

SPECIFICATION_VERSION

public static final Attributes.Name SPECIFICATION_VERSION

Manifest Attribute Name object for SPECIFICATION_VERSION.

SPECIFICATION_VENDOR

public static final Attributes.Name SPECIFICATION_VENDOR

Manifest Attribute Name object for SPECIFICATION_VENDOR.

IMPLEMENTATION_VERSION

public static final Attributes.Name IMPLEMENTATION_VERSION

Manifest Attribute Name object for IMPLEMENTATION_VERSION.

IMPLEMENTATION_VENDOR

public static final Attributes.Name IMPLEMENTATION_VENDOR

Manifest Attribute Name object for IMPLEMENTATION_VENDOR.

IMPLEMENTATION_URL

public static final Attributes.Name IMPLEMENTATION_URL

Manifest Attribute Name object for IMPLEMENTATION_URL.

IMPLEMENTATION_VENDOR_ID

public static final Attributes.Name IMPLEMENTATION_VENDOR_ID

Manifest Attribute Name object for IMPLEMENTATION_VENDOR_ID.

COMPATIBLE

public static final Compatibility COMPATIBLE

Enum indicating that extension is 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.

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.

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.

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

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

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 manifest

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

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

getExtensionName

public String getExtensionName()

Get the name of the extension.

Returns:

the name of the extension

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.

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.

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 specified extension

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.

Overrides:

toString in class Object

Returns:

string representation of object.