1  import java.io.File;

  2  

  3  public class FileFinder

  4  {

  5     private File[] children;

  6  

  7     /**

  8        Constructs a file finder for a given directory tree.

  9        @param startingDirectory the starting directory of the tree

 10     */

 11     public FileFinder(File startingDirectory)

 12     {

 13        children = startingDirectory.listFiles();

 14     }

 15  

 16     /**

 17        Prints all files whose names end in a given extension.

 18        @param extension a file extension (such as ".java")

 19     */

 20     public void find(String extension)

 21     {      

 22        for (File child : children)

 23        {

 24           String fileName = child.toString();

 25           if (child.isDirectory())

 26           {

 27              FileFinder finder = new FileFinder(child);

 28              finder.find(extension);

 29           }

 30           else if (fileName.endsWith(extension))

 31           {

 32              System.out.println(fileName);

 33           }

 34        }

 35     }

 36  }