content: /*
   * 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;
  
  /**
   * Metadata for a value that cannot <code>null</code>. All Metadata subtypes
   * extend this type except for {@link NullMetadata}.
   * 
   * <p>
   * This Metadata type is used for keys in Maps because they cannot be
   * <code>null</code>.
   * 
   * @ThreadSafe
   * @version $Revision$
   */
  public interface NonNullMetadata extends Metadata {
  	// marker interface
  }
  