| /******************************************************************************* |
| * Copyright (c) 2009, 2010 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.e4.core.di.suppliers; |
| |
| import org.osgi.framework.BundleContext; |
| |
| /** |
| * The base class for an "object supplier" - something that knows how to |
| * instantiate objects corresponding to the object descriptor. Extended object |
| * suppliers work as a part of an injector, filling in values that primary |
| * suppliers don't know about. |
| * <p> |
| * If the supplier is asked to track changes, it should notify requestor |
| * whenever any of the objects produced by the |
| * {@link #get(IObjectDescriptor, IRequestor, boolean, boolean)} method change. |
| * The supplier can do this by performing calls to the |
| * {@link IRequestor#resolveArguments(boolean)} and |
| * {@link IRequestor#execute()}. |
| * </p> |
| * |
| * @see IRequestor#resolveArguments(boolean) |
| * @see IRequestor#execute() |
| * @since 1.7.0 |
| */ |
| abstract public class ExtendedObjectSupplier { |
| |
| /** |
| * The OSGi service name for an object provider service. This name can be used to obtain |
| * instances of the service. |
| * |
| * @see BundleContext#getServiceReference(String) |
| */ |
| public static final String SERVICE_NAME = ExtendedObjectSupplier.class.getName(); |
| |
| /** |
| * An OSGi service property used to indicate the context key this function should be registered |
| * in. |
| * |
| * @see BundleContext#getServiceReference(String) |
| */ |
| public static final String SERVICE_CONTEXT_KEY = "dependency.injection.annotation"; //$NON-NLS-1$ |
| |
| /** |
| * Constructs a new instance of an extended object supplier. |
| */ |
| public ExtendedObjectSupplier() { |
| // placeholder |
| } |
| |
| /** |
| * This method is called by the dependency injection mechanism to obtain an object corresponding |
| * to the object descriptor. If the supplier is asked to track changes, it should notify requestor |
| * whenever it detects a change that would result in a different result produced by this method. |
| * @param descriptor descriptor of the object requested by the requestor |
| * @param requestor the originator of this request |
| * @param track <code>true</code> if the object suppliers should notify requestor of |
| * changes to the returned objects; <code>false</code> otherwise |
| * @param group <code>true</code> if the change notifications can be grouped; |
| * <code>false</code> otherwise |
| * @return object corresponding to the object descriptor |
| */ |
| abstract public Object get(IObjectDescriptor descriptor, IRequestor requestor, boolean track, boolean group); |
| |
| } |