| /* |
| * Copyright (c) OSGi Alliance (2008, 2009). All Rights Reserved. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.osgi.service.blueprint.reflect; |
| |
| import java.util.Collection; |
| |
| /** |
| * Metadata for a reference to an OSGi service. This is the base type for |
| * {@link ReferenceListMetadata} and {@link ReferenceMetadata}. |
| * |
| * @ThreadSafe |
| * @version $Revision: 792499 $ |
| */ |
| public interface ServiceReferenceMetadata extends ComponentMetadata { |
| |
| /** |
| * A matching service is required at all times. |
| * |
| * @see #getAvailability() |
| */ |
| static final int AVAILABILITY_MANDATORY = 1; |
| |
| /** |
| * A matching service is not required to be present. |
| * |
| * @see #getAvailability() |
| */ |
| static final int AVAILABILITY_OPTIONAL = 2; |
| |
| /** |
| * Return whether or not a matching service is required at all times. |
| * |
| * This is specified in the <code>availability</code> attribute of the |
| * service reference. |
| * |
| * @return Whether or not a matching service is required at all times. |
| * @see #AVAILABILITY_MANDATORY |
| * @see #AVAILABILITY_OPTIONAL |
| */ |
| int getAvailability(); |
| |
| /** |
| * Return the name of the interface type that a matching service must |
| * support. |
| * |
| * This is specified in the <code>interface</code> attribute of the service |
| * reference. |
| * |
| * @return The name of the interface type that a matching service must |
| * support or <code>null</code> when no interface name is specified. |
| */ |
| String getInterface(); |
| |
| /** |
| * Return the value of the <code>component-name</code> attribute of the |
| * service reference. This specifies the id of a component that is |
| * registered in the service registry. This will create an automatic filter, |
| * appended with the filter if set, to select this component based on its |
| * automatic <code>id</code> attribute. |
| * |
| * @return The value of the <code>component-name</code> attribute of the |
| * service reference or <code>null</code> if the attribute is not |
| * specified. |
| */ |
| String getComponentName(); |
| |
| /** |
| * Return the filter expression that a matching service must match. |
| * |
| * This is specified by the <code>filter</code> attribute of the service |
| * reference. |
| * |
| * @return The filter expression that a matching service must match or |
| * <code>null</code> if a filter is not specified. |
| */ |
| String getFilter(); |
| |
| /** |
| * Return the reference listeners to receive bind and unbind events. |
| * |
| * This is specified by the <code>reference-listener</code> elements of the |
| * service reference. |
| * |
| * @return An immutable Collection of {@link ReferenceListener} objects to |
| * receive bind and unbind events. The Collection is empty if no |
| * reference listeners are specified for the service reference. |
| */ |
| Collection<ReferenceListener> getReferenceListeners(); |
| } |