org.eclipse.platform/org.eclipse.equinox.registry/3.8.600 : org/eclipse/core/runtime/IExtensionPoint.java

IExtensionPoint

http://www.eclipse.org/platform: Extension Registry Support (Eclipse Foundation)

Eclipse Public License - v 2.0

Copyright (c) 2000, 2009 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2009 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.core.runtime;

An extension point declared in a plug-in.
Except for the list of extensions plugged in to it, the information
available for an extension point is obtained from the declaring plug-in's
manifest (plugin.xml) file.
 These registry objects are intended for relatively short-term use. Clients that deal with these objects must be aware that they may become invalid if the declaring plug-in is updated or uninstalled. If this happens, all methods except isValid() will throw InvalidRegistryObjectException. For extension point objects, the most common case is code in a plug-in dealing with one of the extension points it declares. These extension point objects are guaranteed to be valid while the plug-in is active. Code in a plug-in that has declared that it is not dynamic aware (or not declared anything) can also safely ignore this issue, since the registry would not be modified while it is active. However, code in a plug-in that declares that it is dynamic aware must be careful if it access the extension point object of a different plug-in, because it's at risk if that other plug-in is removed. Similarly, tools that analyze or display the extension registry are vulnerable. Client code can pre-test for invalid objects by calling isValid(), which never throws this exception. However, pre-tests are usually not sufficient because of the possibility of the extension point object becoming invalid as a result of a concurrent activity. At-risk clients must treat InvalidRegistryObjectException as if it were a checked exception.
Also, such clients should probably register a listener with the extension registry
so that they receive notification of any changes to the registry.

This interface can be used without OSGi running.

This interface is not intended to be implemented by clients.

@noimplement This interface is not intended to be implemented by clients./**
 * An extension point declared in a plug-in.
 * Except for the list of extensions plugged in to it, the information
 * available for an extension point is obtained from the declaring plug-in's
 * manifest (<code>plugin.xml</code>) file.
 * <p>
 * These registry objects are intended for relatively short-term use. Clients that
 * deal with these objects must be aware that they may become invalid if the
 * declaring plug-in is updated or uninstalled. If this happens, all methods except
 * {@link #isValid()} will throw {@link InvalidRegistryObjectException}.
 * For extension point objects, the most common case is code in a plug-in dealing
 * with one of the extension points it declares. These extension point objects are
 * guaranteed to be valid while the plug-in is active. Code in a plug-in that has
 * declared that it is not dynamic aware (or not declared anything) can also safely
 * ignore this issue, since the registry would not be modified while it is
 * active. However, code in a plug-in that declares that it is dynamic aware
 * must be careful if it access the extension point object of a different plug-in,
 * because it's at risk if that other plug-in is removed. Similarly,
 * tools that analyze or display the extension registry are vulnerable.
 * Client code can pre-test for invalid objects by calling {@link #isValid()},
 * which never throws this exception. However, pre-tests are usually not sufficient
 * because of the possibility of the extension point object becoming invalid as a
 * result of a concurrent activity. At-risk clients must treat
 * <code>InvalidRegistryObjectException</code> as if it were a checked exception.
 * Also, such clients should probably register a listener with the extension registry
 * so that they receive notification of any changes to the registry.
 * </p><p>
 * This interface can be used without OSGi running.
 * </p><p>
 * This interface is not intended to be implemented by clients.
 * </p>
 * @noimplement This interface is not intended to be implemented by clients.
 */
public interface IExtensionPoint {
	Returns all configuration elements from all extensions configured
into this extension point. Returns an empty array if this extension
point has no extensions configured, or none of the extensions
contain configuration elements.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the configuration elements for all extension configured
  into this extension point/**
	 * Returns all configuration elements from all extensions configured
	 * into this extension point. Returns an empty array if this extension
	 * point has no extensions configured, or none of the extensions
	 * contain configuration elements.
	 *
	 * @return the configuration elements for all extension configured
	 *   into this extension point
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public IConfigurationElement[] getConfigurationElements() throws InvalidRegistryObjectException;

	Returns the namespace for this extension point. This value can be used
in various global facilities to discover this extension point's provider.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
See Also: IExtensionRegistry
Returns: the namespace for this extension point
Since: 3.0
Deprecated: As namespace is no longer restricted to the contributor name, use getNamespaceIdentifier() to obtain namespace name or getContributor() to get the name of the contributor of this registry element. 
In the past namespace was dictated by the name of the bundle. If bundle org.abc
contributed registry element with Id of MyId, the namespace of
the element was always set to org.abc, producing the qualified name of
org.abc.MyId.
 The namespace used to be the same as the bundle name. As a result, the getNamespace() method was used both to obtain the name of the bundle and to obtain the namespace of a registry element. 

Since 3.2, the extension registry allows elements to specify qualified name. The extension point
of the plug-in org.abc could specify org.zzz.MyExtPoint as
an Id. In this case, namespace name is org.zzz, but the contributor
name is org.abc.

(The use of a simple Id is still a preferred way. Whenever possible, specify only the simple
Id and let runtime take care of the rest.)
 If your code used the getNamespace() to obtain the name of the contributing bundle, use getContributor(). The typical usage pattern here is to find a bundle name to obtain some information from the corresponding OSGi bundle. For example, deducing the file location specified as a relative path to the bundle install location would fall into this group. 
 If your code used the getNamespace() to obtain the namespace of the registry element, use getNamespaceIdentifier(). Typically, this is the case when code is trying to process registry elements belonging to some logical group. For example, processing notifications for all elements belonging to the org.abc namespace would fall into this category.
/**
	 * Returns the namespace for this extension point. This value can be used
	 * in various global facilities to discover this extension point's provider.
	 *
	 * @return the namespace for this extension point
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 * @see IExtensionRegistry
	 * @since 3.0
	 * @deprecated As namespace is no longer restricted to the contributor name,
	 * 	use {@link #getNamespaceIdentifier()} to obtain namespace name or {@link #getContributor()}
	 * 	to get the name of the contributor of this registry element.
	 * <p>
	 * In the past namespace was dictated by the name of the bundle. If bundle <code>org.abc</code>
	 * contributed registry element with Id of <code>MyId</code>, the namespace of
	 * the element was always set to <code>org.abc</code>, producing the qualified name of
	 * <code>org.abc.MyId</code>.
	 * </p><p>
	 * The namespace used to be the same as the bundle name. As a result, the {@link #getNamespace()}
	 * method was used both to obtain the name of the bundle and to obtain the namespace of a registry
	 * element.
	 * </p><p>
	 * Since 3.2, the extension registry allows elements to specify qualified name. The extension point
	 * of the plug-in <code>org.abc</code> could specify <code>org.zzz.MyExtPoint</code> as
	 * an Id. In this case, namespace name is <code>org.zzz</code>, but the contributor
	 * name is <code>org.abc</code>.
	 * </p><p>
	 * (The use of a simple Id is still a preferred way. Whenever possible, specify only the simple
	 * Id and let runtime take care of the rest.)
	 * </p><p>
	 * If your code used the {@link #getNamespace()} to obtain the name of the contributing bundle,
	 * use {@link #getContributor()}. The typical usage pattern here is to find a bundle name to obtain
	 * some information from the corresponding OSGi bundle. For example, deducing the file location
	 * specified as a relative path to the bundle install location would fall into this group.
	 * </p><p>
	 * If your code used the {@link #getNamespace()} to obtain the namespace of the registry element,
	 * use {@link #getNamespaceIdentifier()}. Typically, this is the case when code is trying to process
	 * registry elements belonging to some logical group. For example, processing notifications for all
	 * elements belonging to the <code>org.abc</code> namespace would fall into this category.
	 * </p>
	 */
	public String getNamespace() throws InvalidRegistryObjectException;

	Returns the namespace name for this extension point.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the namespace name for this extension point
Since: org.eclipse.equinox.registry 3.2/**
	 * Returns the namespace name for this extension point.
	 *
	 * @return the namespace name for this extension point
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 * @since org.eclipse.equinox.registry 3.2
	 */
	public String getNamespaceIdentifier() throws InvalidRegistryObjectException;

	Returns the contributor of this extension point.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the contributor for this extension point
Since: org.eclipse.equinox.registry 3.2/**
	 * Returns the contributor of this extension point.
	 *
	 * @return the contributor for this extension point
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 * @since org.eclipse.equinox.registry 3.2
	 */
	public IContributor getContributor() throws InvalidRegistryObjectException;

	Returns the extension with the given unique identifier configured into
this extension point, or null if there is no such extension.
Since an extension might not have an identifier, some extensions
can only be found via the getExtensions method.
Params: extensionId – the unique identifier of an extension
	(e.g. "com.example.acme.main").
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: an extension, or null/**
	 * Returns the extension with the given unique identifier configured into
	 * this extension point, or <code>null</code> if there is no such extension.
	 * Since an extension might not have an identifier, some extensions
	 * can only be found via the <code>getExtensions</code> method.
	 *
	 * @param extensionId the unique identifier of an extension
	 *		(e.g. <code>"com.example.acme.main"</code>).
	 * @return an extension, or <code>null</code>
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public IExtension getExtension(String extensionId) throws InvalidRegistryObjectException;

	Returns all extensions configured into this extension point.
Returns an empty array if this extension point has no extensions.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the extensions configured into this extension point/**
	 * Returns all extensions configured into this extension point.
	 * Returns an empty array if this extension point has no extensions.
	 *
	 * @return the extensions configured into this extension point
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public IExtension[] getExtensions() throws InvalidRegistryObjectException;

	Returns a displayable label for this extension point.
Returns the empty string if no label for this extension point
is specified in the plug-in manifest file.
 Note that any translation specified in the plug-in manifest
file is automatically applied.

Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: a displayable string label for this extension point,
   possibly the empty string/**
	 * Returns a displayable label for this extension point.
	 * Returns the empty string if no label for this extension point
	 * is specified in the plug-in manifest file.
	 * <p> Note that any translation specified in the plug-in manifest
	 * file is automatically applied.
	 * </p>
	 *
	 * @return a displayable string label for this extension point,
	 *    possibly the empty string
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public String getLabel() throws InvalidRegistryObjectException;

	When multi-language support is enabled, this method returns a displayable label
for this extension point in the specified locale.
Returns the empty string if no label for this extension point
is specified in the plug-in manifest file.

The locale matching tries to find the best match between available translations and
the requested locale, falling back to a more generic locale ("en") when the specific
locale ("en_US") is not available.
 If multi-language support is not enabled, this method is equivalent to the method getLabel(). 
Params: locale – the requested locale
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
See Also: IExtensionRegistry.isMultiLanguage()
Returns: a displayable string label for this extension point,
   possibly the empty string
Since: 3.5/**
	 * When multi-language support is enabled, this method returns a displayable label
	 * for this extension point in the specified locale.
	 * Returns the empty string if no label for this extension point
	 * is specified in the plug-in manifest file.
	 * <p>
	 * The locale matching tries to find the best match between available translations and
	 * the requested locale, falling back to a more generic locale ("en") when the specific
	 * locale ("en_US") is not available.
	 * </p><p>
	 * If multi-language support is not enabled, this method is equivalent to the method
	 * {@link #getLabel()}.
	 * </p>
	 * @param locale the requested locale
	 * @return a displayable string label for this extension point,
	 *    possibly the empty string
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 * @see IExtensionRegistry#isMultiLanguage()
	 * @since 3.5
	 */
	public String getLabel(String locale) throws InvalidRegistryObjectException;

	Returns reference to the extension point schema. The schema
reference is returned as a URL path relative to the plug-in
installation URL.
Returns the empty string if no schema for this extension point
is specified in the plug-in manifest file.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: a relative URL path, or an empty string/**
	 * Returns reference to the extension point schema. The schema
	 * reference is returned as a URL path relative to the plug-in
	 * installation URL.
	 * Returns the empty string if no schema for this extension point
	 * is specified in the plug-in manifest file.
	 *
	 * @return a relative URL path, or an empty string
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public String getSchemaReference() throws InvalidRegistryObjectException;

	Returns the simple identifier of this extension point.
This identifier is a non-empty string containing no
period characters ('.') and is guaranteed
to be unique within the namespace.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the simple identifier of the extension point (e.g. "builders")/**
	 * Returns the simple identifier of this extension point.
	 * This identifier is a non-empty string containing no
	 * period characters (<code>'.'</code>) and is guaranteed
	 * to be unique within the namespace.
	 *
	 * @return the simple identifier of the extension point (e.g. <code>"builders"</code>)
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public String getSimpleIdentifier() throws InvalidRegistryObjectException;

	Returns the unique identifier of this extension point.
This identifier is unique within the plug-in registry, and
is composed of the namespace for this extension point
and this extension point's simple identifier.
Throws: InvalidRegistryObjectException – if this extension point is no longer valid
Returns: the unique identifier of the extension point
   (e.g. "org.eclipse.core.resources.builders")/**
	 * Returns the unique identifier of this extension point.
	 * This identifier is unique within the plug-in registry, and
	 * is composed of the namespace for this extension point
	 * and this extension point's simple identifier.
	 *
	 *
	 * @return the unique identifier of the extension point
	 *    (e.g. <code>"org.eclipse.core.resources.builders"</code>)
	 * @throws InvalidRegistryObjectException if this extension point is no longer valid
	 */
	public String getUniqueIdentifier() throws InvalidRegistryObjectException;

	/* (non-javadoc)
	 * @see Object#equals(java.lang.Object)
	 */
	@Override
	public boolean equals(Object o);

	Returns whether this extension point object is valid.
Returns: true if the object is valid, and false
if it is no longer valid
Since: 3.1/**
	 * Returns whether this extension point object is valid.
	 *
	 * @return <code>true</code> if the object is valid, and <code>false</code>
	 * if it is no longer valid
	 * @since 3.1
	 */
	public boolean isValid();
}

Throws:	InvalidRegistryObjectException – if this extension point is no longer valid
Returns:	the configuration elements for all extension configured into this extension point

Throws:	InvalidRegistryObjectException – if this extension point is no longer valid
See Also:	IExtensionRegistry
Returns:	the namespace for this extension point
Since:	3.0
Deprecated:	As namespace is no longer restricted to the contributor name, use `getNamespaceIdentifier()` to obtain namespace name or `getContributor()` to get the name of the contributor of this registry element. In the past namespace was dictated by the name of the bundle. If bundle `org.abc` contributed registry element with Id of `MyId`, the namespace of the element was always set to `org.abc`, producing the qualified name of `org.abc.MyId`. The namespace used to be the same as the bundle name. As a result, the `getNamespace()` method was used both to obtain the name of the bundle and to obtain the namespace of a registry element. Since 3.2, the extension registry allows elements to specify qualified name. The extension point of the plug-in `org.abc` could specify `org.zzz.MyExtPoint` as an Id. In this case, namespace name is `org.zzz`, but the contributor name is `org.abc`. (The use of a simple Id is still a preferred way. Whenever possible, specify only the simple Id and let runtime take care of the rest.) If your code used the `getNamespace()` to obtain the name of the contributing bundle, use `getContributor()`. The typical usage pattern here is to find a bundle name to obtain some information from the corresponding OSGi bundle. For example, deducing the file location specified as a relative path to the bundle install location would fall into this group. If your code used the `getNamespace()` to obtain the namespace of the registry element, use `getNamespaceIdentifier()`. Typically, this is the case when code is trying to process registry elements belonging to some logical group. For example, processing notifications for all elements belonging to the `org.abc` namespace would fall into this category.

Params:	extensionId – the unique identifier of an extension (e.g. `"com.example.acme.main"`).
Throws:	InvalidRegistryObjectException – if this extension point is no longer valid
Returns:	an extension, or `null`

Params:	locale – the requested locale
Throws:	InvalidRegistryObjectException – if this extension point is no longer valid
See Also:	IExtensionRegistry.isMultiLanguage()
Returns:	a displayable string label for this extension point, possibly the empty string
Since:	3.5

Returns:	`true` if the object is valid, and `false` if it is no longer valid
Since:	3.1

/

org.eclipse.platform/ org.eclipse.equinox.registry/ 3.8.600/ org/eclipse/core/runtime/IExtensionPoint.java