content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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
   *
   *     http://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.apache.shiro.lang.util;
  
  import org.apache.shiro.lang.ShiroException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.Collection;
  
  
  /**
   * Utility class to help call {@link org.apache.shiro.lang.util.Initializable#init() Initializable.init()} and
   * {@link org.apache.shiro.lang.util.Destroyable#destroy() Destroyable.destroy()} methods cleanly on any object.
   *
   * @since 0.2
   */
  public abstract class LifecycleUtils {
  
      private static final Logger log = LoggerFactory.getLogger(LifecycleUtils.class);
  
      public static void init(Object o) throws ShiroException {
          if (o instanceof Initializable) {
              init((Initializable) o);
          }
      }
  
      public static void init(Initializable initializable) throws ShiroException {
          initializable.init();
      }
  
      /**
       * Calls {@link #init(Object) init} for each object in the collection.  If the collection is {@code null} or empty,
       * this method returns quietly.
       *
       * @param c the collection containing objects to {@link #init init}.
       * @throws ShiroException if unable to initialize one or more instances.
       * @since 0.9
       */
      public static void init(Collection c) throws ShiroException {
          if (c == null || c.isEmpty()) {
              return;
          }
          for (Object o : c) {
              init(o);
          }
      }
  
      public static void destroy(Object o) {
          if (o instanceof Destroyable) {
              destroy((Destroyable) o);
          } else if (o instanceof Collection) {
              destroy((Collection)o);
          }
      }
  
      public static void destroy(Destroyable d) {
          if (d != null) {
              try {
                  d.destroy();
              } catch (Throwable t) {
                  if (log.isDebugEnabled()) {
                      String msg = "Unable to cleanly destroy instance [" + d + "] of type [" + d.getClass().getName() + "].";
                      log.debug(msg, t);
                  }
              }
          }
      }
  
      /**
       * Calls {@link #destroy(Object) destroy} for each object in the collection.
       * If the collection is {@code null} or empty, this method returns quietly.
       *
       * @param c the collection of objects to destroy.
       * @since 0.9
       */
      public static void destroy(Collection c) {
          if (c == null || c.isEmpty()) {
              return;
          }
  
          for (Object o : c) {
              destroy(o);
          }
      }
  }
  