| /******************************************************************************* |
| * Copyright (c) 2000, 2004 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-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. Similiarly, |
| * 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 is not intended to be implemented by clients. |
| * </p> |
| */ |
| 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 descriptor of the plug-in that declares this extension point. |
| * |
| * @return the plug-in that declares this extension point |
| * @throws InvalidRegistryObjectException if this extension point is no longer valid |
| * @deprecated IPluginDescriptor is not part of the new runtime and its function |
| * has been split over several parts of the new runtime. This method |
| * is not available (returns null) if the compatibility layer is not installed. Use getNamespace() |
| * to get the symbolic id of the declaring plugin. See {@link IPluginDescriptor} to see how to |
| * update your usecases. |
| */ |
| public IPluginDescriptor getDeclaringPluginDescriptor() 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. |
| * <p> |
| * <b>Note</b>: This is an early access API to the new OSGI-based Eclipse 3.0 |
| * Platform Runtime. Because the APIs for the new runtime have not yet been fully |
| * stabilized, they should only be used by clients needing to take particular |
| * advantage of new OSGI-specific functionality, and only then with the understanding |
| * that these APIs may well change in incompatible ways until they reach |
| * their finished, stable form (post-3.0). </p> |
| * |
| * @return the namespace for this extension point |
| * @throws InvalidRegistryObjectException if this extension point is no longer valid |
| * @see Platform#getBundle(String) |
| * @see IExtensionRegistry |
| * @since 3.0 |
| */ |
| public String getNamespace() 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; |
| |
| /** |
| * 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 defining plug-in. |
| * |
| * @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(); |
| } |