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     */
020    package org.apache.directory.server.schema.registries;
021    
022    
023    import java.util.Collection;
024    import java.util.Properties;
025    
026    import org.apache.directory.server.schema.bootstrap.Schema;
027    
028    
029    /**
030     * Loads schemas into registres.
031     *
032     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
033     * @version $Rev$
034     */
035    public interface SchemaLoader
036    {
037        /**
038         * Sets listener used to notify of newly loaded schemas.
039         * 
040         * @param listener the listener to notify (only one is enough for us)
041         * @note probably should have used the observer pattern here 
042         */
043        public void setListener( SchemaLoaderListener listener );
044        
045        /**
046         * Gets a schema object based on it's name.
047         * 
048         * @param schemaName the name of the schema to load
049         * @return the Schema object associated with the name
050         * @throws NamingException if any problems while trying to find the associated Schema
051         */
052        Schema getSchema( String schemaName ) throws Exception;
053        
054        /**
055         * Gets a schema object based on it's name and some properties.
056         * 
057         * @param schemaName the name of the schema to load
058         * @param schemaProperties the properties associated with that schema to facilitate locating/loading it
059         * @return the Schema object associated with the name
060         * @throws NamingException if any problems while trying to find the associated Schema
061         */
062        Schema getSchema( String schemaName, Properties schemaProperties ) throws Exception;
063        
064        /**
065         * Loads a collection of schemas.  A best effort should be made to load the dependended 
066         * schemas that these schemas may rely on even if they are not included in the collection.
067         * 
068         * @param schemas the collection of schemas to load
069         * @param registries the registries to populate with these schemas
070         * @throws NamingException if any kind of problems are encountered during the load
071         */
072        void loadWithDependencies( Collection<Schema> schemas, Registries registries ) throws Exception;
073        
074        /**
075         * Loads a single schema at least and possibly it's dependencies.  
076         * 
077         * @param schemas the schema to load
078         * @param registries the registries to populate with these schemas
079         * @throws NamingException if any kind of problems are encountered during the load
080         */
081        void loadWithDependencies( Schema schemas, Registries registries ) throws Exception;
082        
083        /**
084         * Loads a single schema.  Do not try to resolve dependencies while implementing this method.
085         * 
086         * @param schema the schema to load
087         * @param registries the registries to populate with these schemas
088         * @param isDepLoad tells the loader if this load request is to satisfy a dependency
089         * @throws NamingException if any kind of problems are encountered during the load
090         */
091        void load( Schema schema, Registries registries, boolean isDepLoad ) throws Exception;
092    }