Java tutorial
/* * Copyright 2002-2018 the original author or authors. * * 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 * * https://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.springframework.jndi; import javax.naming.Context; import javax.naming.NamingException; import org.springframework.lang.Nullable; /** * Callback interface to be implemented by classes that need to perform an * operation (such as a lookup) in a JNDI context. This callback approach * is valuable in simplifying error handling, which is performed by the * JndiTemplate class. This is a similar to JdbcTemplate's approach. * * <p>Note that there is hardly any need to implement this callback * interface, as JndiTemplate provides all usual JNDI operations via * convenience methods. * * @author Rod Johnson * @param <T> the resulting object type * @see JndiTemplate * @see org.springframework.jdbc.core.JdbcTemplate */ @FunctionalInterface public interface JndiCallback<T> { /** * Do something with the given JNDI context. * <p>Implementations don't need to worry about error handling * or cleanup, as the JndiTemplate class will handle this. * @param ctx the current JNDI context * @throws NamingException if thrown by JNDI methods * @return a result object, or {@code null} */ @Nullable T doInContext(Context ctx) throws NamingException; }