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.file;
  
  import java.util.Comparator;
  import java.util.Iterator;
  import java.util.Map;
  
  import org.apache.camel.CamelContext;
  import org.apache.camel.Exchange;
  import org.apache.camel.support.EndpointHelper;
  import org.apache.camel.support.HealthCheckComponent;
  import org.apache.camel.support.ObjectHelper;
  import org.apache.camel.util.CastUtils;
  import org.apache.camel.util.StringHelper;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import static org.apache.camel.util.ObjectHelper.isNotEmpty;
  
  /**
   * Base class file component. To be extended.
   */
  public abstract class GenericFileComponent<T> extends HealthCheckComponent {
  
      protected Logger log = LoggerFactory.getLogger(getClass());
  
      protected GenericFileComponent() {
      }
  
      protected GenericFileComponent(CamelContext context) {
          super(context);
      }
  
      @Override
      protected GenericFileEndpoint<T> createEndpoint(String uri, String remaining, Map<String, Object> parameters)
              throws Exception {
  
          // create the correct endpoint based on the protocol
          final GenericFileEndpoint<T> endpoint;
  
          // call to subclasses to build their custom version of a
          // GenericFileEndpoint
          endpoint = buildFileEndpoint(uri, remaining, parameters);
  
          // sort by using file language
          String sortBy = getAndRemoveParameter(parameters, "sortBy", String.class);
          if (isNotEmpty(sortBy) && !EndpointHelper.isReferenceParameter(sortBy)) {
              // we support nested sort groups so they should be chained
              String[] groups = sortBy.split(";");
              Iterator<String> it = CastUtils.cast(ObjectHelper.createIterator(groups));
              Comparator<Exchange> comparator = createSortByComparator(it);
              endpoint.setSortBy(comparator);
          }
          setProperties(endpoint, parameters);
  
          afterPropertiesSet(endpoint);
  
          return endpoint;
      }
  
      /**
       * A factory method for derived file components to create the endpoint
       *
       * @param  uri        the full URI of the endpoint
       * @param  remaining  the remaining part of the URI without the query parameters or component prefix
       * @param  parameters the optional parameters passed in
       * @return            a newly created endpoint or null if the endpoint cannot be created based on the inputs
       * @throws Exception  can be thrown
       */
      protected abstract GenericFileEndpoint<T> buildFileEndpoint(String uri, String remaining, Map<String, Object> parameters)
              throws Exception;
  
      /**
       * A factory method for derived file components to perform validation of properties
       *
       * @param  endpoint  the endpoint
       * @throws Exception can be thrown in case of validation errors
       */
      protected abstract void afterPropertiesSet(GenericFileEndpoint<T> endpoint) throws Exception;
  
      /**
       * Helper to create a sort comparator
       *
       * @param  it iterator
       * @return    Comparator<Exchange>
       */
      private Comparator<Exchange> createSortByComparator(Iterator<String> it) {
          if (!it.hasNext()) {
              return null;
          }
  
          String group = it.next();
  
          boolean reverse = group.startsWith("reverse:");
          String reminder = reverse ? ifStartsWithReturnRemainder("reverse:", group) : group;
  
          boolean ignoreCase = reminder.startsWith("ignoreCase:");
          reminder = ignoreCase ? ifStartsWithReturnRemainder("ignoreCase:", reminder) : reminder;
  
          StringHelper.notEmpty(reminder, "sortBy expression", this);
  
          // recursive add nested sorters
          return GenericFileDefaultSorter.sortByFileLanguage(getCamelContext(), reminder, reverse, ignoreCase,
                  createSortByComparator(it));
      }
  }
  