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.camel.component.dropbox.util;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URL;
  import java.util.Properties;
  import java.util.concurrent.locks.Lock;
  import java.util.concurrent.locks.ReentrantLock;
  
  public final class DropboxPropertyManager {
  
      private static final Lock LOCK = new ReentrantLock();
      private static Properties properties;
      private static DropboxPropertyManager instance;
  
      private DropboxPropertyManager() {
      }
  
      public static DropboxPropertyManager getInstance() throws Exception {
          LOCK.lock();
          try {
              if (instance == null) {
                  instance = new DropboxPropertyManager();
                  properties = loadProperties();
              }
              return instance;
          } finally {
              LOCK.unlock();
          }
      }
  
      public String getProperty(String key) {
          return properties.getProperty(key);
      }
  
      private static Properties loadProperties() throws DropboxException {
          URL url = DropboxPropertyManager.class.getResource("/dropbox.properties");
          if (url == null) {
              throw new DropboxException("dropbox.properties could not be found");
          }
          Properties properties = new Properties();
          try (InputStream inStream = url.openStream()) {
              properties.load(inStream);
          } catch (IOException e) {
              throw new DropboxException("dropbox.properties can't be read", e);
          }
  
          return properties;
      }
  }
  