001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *  http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing,
013     * software distributed under the License is distributed on an
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015     * KIND, either express or implied.  See the License for the
016     * specific language governing permissions and limitations
017     * under the License.
018     */
019    package org.apache.directory.server.core.annotations;
020    
021    import java.lang.annotation.ElementType;
022    import java.lang.annotation.Retention;
023    import java.lang.annotation.RetentionPolicy;
024    import java.lang.annotation.Target;
025    
026    import org.apache.directory.server.xdbm.Index;
027    
028    /**
029     * An annotation for the Index creation. It's used when we need to inject an
030     * indexed attribute into a given partition. Here is an exemple :
031     * <pre>
032     * @CreatePartition(
033     *     name = "example",
034     *     @Indexes( {
035     *         @CreateIndex( attribute = "cn" ),
036     *         @CreateIndex( attribute = "sn', cacheSize = "100" )
037     *     })
038     * )
039     * </pre>
040     * There is one more parameter, the 'factory', which can be used to declare
041     * a specific kind of Index. It defaults to JdbmIndex.
042     *
043     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
044     * @version $Rev$, $Date$
045     */
046    @Retention(RetentionPolicy.RUNTIME)
047    @Target( {ElementType.METHOD, ElementType.TYPE } )
048    public @interface CreateIndex
049    {
050        /** The index implementation class */
051        @SuppressWarnings("unchecked")
052        Class<? extends Index> type() default Index.class;
053        
054        /** The cache size */
055        int cacheSize() default 1000;
056        
057        /** The indexed attribute */
058        String attribute();
059    }