| /******************************************************************************* |
| * Copyright (c) 2000, 2009 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * 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 (<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. |
| * |
| * @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. |
| * |
| * @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. |
| * |
| * @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. |
| * |
| * @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 <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. |
| * |
| * @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. |
| * <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. |
| * <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. |
| * |
| * @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 (<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. |
| * |
| * |
| * @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) |
| */ |
| public boolean equals(Object o); |
| |
| /** |
| * 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(); |
| } |