/*

  * 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.commons.pipeline.stage;

 import java.io.File;

 import java.util.regex.Pattern;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.apache.commons.pipeline.StageException;

 import org.apache.commons.pipeline.validation.ConsumedTypes;

 import org.apache.commons.pipeline.validation.ProducedTypes;

 /**

  * <p>This {@link org.apache.commons.pipeline.Pipeline$Stage Stage} is used

  * to recursively find (non-directory) files that match the specified regex.</p>

  *

  * <p>File elements in the stage's queue will be recursively searched with the

  * resulting File objects placed on the subsequent stage's queue.</p>

  */

 @ConsumedTypes({String.class, File.class})

 @ProducedTypes(File.class)

 public class FileFinderStage extends BaseStage {

     private final Log log = LogFactory.getLog(FileFinderStage.class);

     private String filePattern = ".*";

     Pattern pattern;

     /** Creates a new instance of FileFinder */

     public FileFinderStage() { }

     /**

      * Precompiles the regex pattern for matching against filenames

      */

     public void preprocess() throws StageException {

         super.preprocess();

         this.pattern = Pattern.compile(this.filePattern);

     }

     /**

      * This method inspects a File object to determine if

      * it matches this FileFinder's filePattern property. If the File

      * represents a directory, it recursively searches that directory and

      * all subdirectories for matching files. Matched files are placed

      * on the next stage's queue.

      */

     public void process(Object obj) {

         File file = (obj instanceof String) ? new File((String) obj) : (File) obj;        

         log.debug("Examining file " + file.getAbsolutePath());

         if (!file.exists()) {

             log.info("File " + file + " does not exist.");

         } else if (file.isDirectory()) {

             File[] files = file.listFiles();

             log.debug(file.getName() + " is a directory, processing " + files.length + " files within.");

             for (int i = 0; i < files.length; i++) {

                 process(files[i]);

             }

         } else if (this.pattern.matcher(file.getName()).matches()){

             this.emit(file);

         }

         }

     /** Getter for property filePattern.

      * @return Value of property filePattern.

      *

      */

     public String getFilePattern() {

         return this.filePattern;

     }

     /** Setter for property filePattern.

      * @param pattern Value of property filePattern.

      *

      */

     public void setFilePattern(String pattern) {

         this.filePattern = pattern;

     }    

 }