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/* * 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.dao.support; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.BeanInitializationException; import org.springframework.beans.factory.InitializingBean; /** * Generic base class for DAOs, defining template methods for DAO initialization. * * <p>Extended by Spring's specific DAO support classes, such as: * JdbcDaoSupport, JdoDaoSupport, etc. * * @author Juergen Hoeller * @since 1.2.2 * @see org.springframework.jdbc.core.support.JdbcDaoSupport */ public abstract class DaoSupport implements InitializingBean { /** Logger available to subclasses. */ protected final Log logger = LogFactory.getLog(getClass()); @Override public final void afterPropertiesSet() throws IllegalArgumentException, BeanInitializationException { // Let abstract subclasses check their configuration. checkDaoConfig(); // Let concrete implementations initialize themselves. try { initDao(); } catch (Exception ex) { throw new BeanInitializationException("Initialization of DAO failed", ex); } } /** * Abstract subclasses must override this to check their configuration. * <p>Implementors should be marked as {@code final} if concrete subclasses * are not supposed to override this template method themselves. * @throws IllegalArgumentException in case of illegal configuration */ protected abstract void checkDaoConfig() throws IllegalArgumentException; /** * Concrete subclasses can override this for custom initialization behavior. * Gets called after population of this instance's bean properties. * @throws Exception if DAO initialization fails * (will be rethrown as a BeanInitializationException) * @see org.springframework.beans.factory.BeanInitializationException */ protected void initDao() throws Exception { } }