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I'm getting the following mentor recommendations: Point 2: The FileManager constructor must initialize the fileList field to a list of Path objects. Point 4: When the collectFileList(Path path) method receives a regular file, the method must add its path relative to rootPath to the fileList field. I though I'd done both of those things

Now let's take care of another part of our archiver that is no less important.
Frequently, users want to create an archive from not just one file, but from an entire folder. In this case, zipping amounts to successively adding a ZipEntry for each file to the archive.
We need to write a FileManager class to get a list of all of the files in some folder. It must have a constructor that has a Path rootPath parameter that indicates the root (the folder containing the files we are interested in), and a List<Path> getFileList() method that should return a list of relative paths for all of the files in rootPath (including files in subfolders). The directory we will search can only be set once in the constructor. So, we can generate the list of files (relative paths) right in the constructor and save it in the class's List<Path> fileList variable.
We just have to decide how to gather up all of the files, even those that might be inside a folder, inside a folder, inside a folder, inside the folder we're looking at. Whoa, we almost entered a recursive loop. But maybe recursion can help us! Let's make a collectFileList(Path path) method that adds all the files inside the path parameter to the class's fileList variable, and calls itself recursively on subfolders.

1. Create a FileManager class with a FileManager(Path rootPath) throws IOException constructor
2. Declare and initialize the following private instance variables:
2.1. Path rootPath - The root path of the directory whose files we are interested in
2.2. List<Path> fileList - The list of relative paths of files inside rootPath
3. Create a getter for fileList
4. Implement a void collectFileList(Path path) throws IOException method that must:
4.1. Check to see if the path parameter is a regular file (use the Files.isRegularFile method), then get its path relative to rootPath and add it to fileList.
4.2. If the path parameter is a directory (determine this using the Files.isDirectory method), then go through all of the directory's contents and call collectFileList(Path path), passing in the discovered elements.
You can go through the all of the directory's contents by first getting a DirectoryStream using the Files class's newDirectoryStream method. Don't forget to close the DirectoryStream.
5. Call the collectFileList(rootPath) method inside the FileManager constructor.
6. Apply everything you've learned about encapsulation to this class.
In completing this task, you wrote an algorithm that traverses a file tree. But Java has a special FileVisitor interface for this. I highly recommend you learn how to use it.

Requirements:

In the root of the task, you must create a FileManager class with a FileManager(Path rootPath) throws IOException constructor.
The FileManager class must have private Path rootPath and List<Path> fileList fields that are initialized inside the constructor.
The FileManager class must have a getter for the fileList field.
You need to implement a private void collectFileList(Path path) throws IOException method in the FileManager class as outlined in the task conditions.
You need to add a call to the collectFileList(rootPath) method inside the FileManager constructor.

package com.codegym.task.task31.task3110; import com.codegym.task.task31.task3110.exception.NoSuchZipFileException; import java.io.IOException; public class Archiver { public static void main(String[] args) throws IOException { Operation operation = null; do { try { operation = askOperation(); CommandExecutor.execute(operation); } catch (NoSuchZipFileException e) { ConsoleHelper.writeMessage("You didn't select an archive or you selected an invalid file."); } catch (Exception e) { ConsoleHelper.writeMessage("An error occurred. Please check the entered data."); } } while (operation != Operation.EXIT); } public static Operation askOperation() throws IOException { ConsoleHelper.writeMessage(""); ConsoleHelper.writeMessage("Select an operation:"); ConsoleHelper.writeMessage(String.format("\t %d - Zip files into an archive", Operation.CREATE.ordinal())); ConsoleHelper.writeMessage(String.format("\t %d - Add a file to an archive", Operation.ADD.ordinal())); ConsoleHelper.writeMessage(String.format("\t %d - Remove a file from an archive", Operation.REMOVE.ordinal())); ConsoleHelper.writeMessage(String.format("\t %d - Extract an archive", Operation.EXTRACT.ordinal())); ConsoleHelper.writeMessage(String.format("\t %d - View the contents of an archive", Operation.CONTENT.ordinal())); ConsoleHelper.writeMessage(String.format("\t %d - Exit", Operation.EXIT.ordinal())); return Operation.values()[ConsoleHelper.readInt()]; } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

2 April 2021, 16:12

solution

Try coding this directly as stated: "Implement a void collectFileList(Path path) throws IOException method that must: 4.1. Check to see if the path parameter is a regular file (use the Files.isRegularFile method), then get its path relative to rootPath and add it to fileList. 4.2. If the path parameter is a directory (determine this using the Files.isDirectory method), then go through all of the directory's contents and call collectFileList(Path path), passing in the discovered elements. So:

private void collectFileList(Path path) throws IOException {
   if (Files.isRegularFile(path)) {
      // 4.1
   }

   if (Files.isDirectory(path)) {
      // 4.2
   }
}

Anthony Chalk

Level 30 , London, United Kingdom

2 April 2021, 16:37

Thank you; was that just CodeGym being pedantic?

Guadalupe Gagnon

Level 37 , Tampa, United States

2 April 2021, 16:42

I think they test the code by actually passing in a regular file to see if it handles it

Guadalupe Gagnon

Level 37 , Tampa, United States

2 April 2021, 16:43

useful

Your code assumes that the first file is always a directory, and if that is the case then it works fine. The task directions hint that it may not always be the case.