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.shiro.jndi;
020    
021    import javax.naming.Context;
022    import javax.naming.NamingException;
023    
024    /**
025     * Callback interface to be implemented by classes that need to perform an
026     * operation (such as a lookup) in a JNDI context. This callback approach
027     * is valuable in simplifying error handling, which is performed by the
028     * JndiTemplate class. This is a similar to JdbcTemplate's approach.
029     *
030     * <p>Note that there is hardly any need to implement this callback
031     * interface, as JndiTemplate provides all usual JNDI operations via
032     * convenience methods.
033     *
034     * <p>Note that this interface is an exact copy of the Spring Framework's identically named interface from
035     * their 2.5.4 distribution - we didn't want to re-invent the wheel, but not require a full dependency on the
036     * Spring framework, nor does Spring make available only its JNDI classes in a small jar, or we would have used that.
037     * Since Shiro is also Apache 2.0 licensed, all regular licenses and conditions and authors have remained in tact.
038     *
039     * @see JndiTemplate
040     */
041    public interface JndiCallback {
042    
043        /**
044         * Do something with the given JNDI context.
045         * Implementations don't need to worry about error handling
046         * or cleanup, as the JndiTemplate class will handle this.
047         *
048         * @param ctx the current JNDI context
049         * @return a result object, or <code>null</code>
050         * @throws NamingException if thrown by JNDI methods
051         */
052        Object doInContext(Context ctx) throws NamingException;
053    
054    }