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 org.apache.camel.Exchange;
  
  /**
   * Represents a pluggable strategy when processing files.
   */
  public interface GenericFileProcessStrategy<T> {
  
      /**
       * Allows custom logic to be run on first poll preparing the strategy, such as removing old lock files etc.
       *
       * @param  operations file operations
       * @param  endpoint   the endpoint
       * @throws Exception  can be thrown in case of errors which causes poll to fail
       */
      void prepareOnStartup(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint) throws Exception;
  
      /**
       * Called when work is about to begin on this file. This method may attempt to acquire some file lock before
       * returning true; returning false if the file lock could not be obtained so that the file should be ignored.
       *
       * @param  operations file operations
       * @param  endpoint   the endpoint
       * @param  exchange   the exchange
       * @param  file       the file
       * @return            true if the file can be processed (such as if a file lock could be obtained)
       * @throws Exception  can be thrown in case of errors
       */
      boolean begin(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, Exchange exchange, GenericFile<T> file)
              throws Exception;
  
      /**
       * Called when a begin is aborted, for example to release any resources which may have been acquired during the
       * {@link #begin(GenericFileOperations, GenericFileEndpoint, org.apache.camel.Exchange, GenericFile)} operation.
       *
       * @param  operations file operations
       * @param  endpoint   the endpoint
       * @param  exchange   the exchange
       * @param  file       the file
       * @throws Exception  can be thrown in case of errors
       */
      void abort(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, Exchange exchange, GenericFile<T> file)
              throws Exception;
  
      /**
       * Releases any file locks and possibly deletes or moves the file after successful processing
       *
       * @param  operations file operations
       * @param  endpoint   the endpoint
       * @param  exchange   the exchange
       * @param  file       the file
       * @throws Exception  can be thrown in case of errors
       */
      void commit(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, Exchange exchange, GenericFile<T> file)
              throws Exception;
  
      /**
       * Releases any file locks and possibly deletes or moves the file after unsuccessful processing
       *
       * @param  operations file operations
       * @param  endpoint   the endpoint
       * @param  exchange   the exchange
       * @param  file       the file
       * @throws Exception  can be thrown in case of errors
       */
      void rollback(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, Exchange exchange, GenericFile<T> file)
              throws Exception;
  
  }
  