Weirdly enough, can't meet the 2nd requirement

Question about the task

Under discussion

I'm working on my ZipFIleManager code now. The requirement I can't pass is, "The extractAll(Path outputFolder) method must throw a NoSuchZipFileException if the archive file does not exist". It's weird, as I'm actually checking for that right at the beginning of the extractAll method:

if (Files.notExists(zipFile)) {
            throw new NoSuchZipFileException();
        }

Am I doing it the wrong way?

It's time to try to extract something. To do this, add a public void extractAll(Path outputFolder) throws Exception method to the ZipFileManager class. The Path outputFolder parameter is the path to which we will extract our archive. You already have extensive experience working with zip entries and streams, so I'll only give you some hints on how to implement this method. You'll have to think carefully about how to do the following:
1. Check whether the zip file exists
2. If the outputFolder directory does not exist, then it needs to be created, along with all the folders that contain it.
3. Inside the archive, some files may be inside folders. In this case, the ZipEntry.getName() method doesn't exactly return the file name, as might be expected from the method name. Instead, it returns the file's relative path inside the archive. This relative path should be retained after the extraction process is complete, but it will become relative to the directory where we have extracted the archive
4. Implement the ZipExtractCommand class's execute() method by analogy with our implementation of ZipCreateCommand. Make a similar try-catch block, and simply change the displayed messages so that the user knows we are currently extracting an archive, and that we need the archive's full name and the directory to which we will extract the archive. Don't forget to call the ZipFileManager class's extractAll method, and not createZip like we did in the ZipCreateCommand
5. Run the program and enjoy the extracted results

Note:
Use Files.newInputStream(Path path) and Files.newOutputStream(Path path) to get read and write streams.

Requirements:

You need to create a public void extractAll(Path outputFolder) throws Exception method in the ZipFileManager class.
The extractAll(Path outputFolder) method must throw a NoSuchZipFileException if the archive file does not exist.
The extractAll(Path outputFolder) method must create the outputFolder directory if it doesn't exist.
The extractAll(Path outputFolder) method must extract all of the files from the archive into the outputFolder directory.
The ZipExtractCommand class's execute() method must get the ZipFileManager object and extract the files to the directory specified by the user.

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

14 March, 13:15

Line 104 of the ZipFileManager class, this may be as simple as having it say "throws NoSuchZipFileException" instead of "throws Exception". Try it out and let me know if that solves the issue; hopefully it does.

Evgeniia Shabaeva

Level 41 , Budapest, Hungary

17 March, 10:40

Unfortunately, in that case the 1st requirement fails, too, alongside with the 2nd one, as I'm supposed to "need to create a public void extractAll(Path outputFolder) throws Exception method in the ZipFileManager class".

Evgeniia Shabaeva

Level 41 , Budapest, Hungary

17 March, 10:53

Like some people who posted in the Help section, I've tried writing:

if (!Files.isRegularFile(zipFile)) ...

instead of

if (Files.notEexists(zipFile)) ...

if (!Files.exists(zipFile)) ...

... and it worked (the task is completed). However, I disagree. The zipFile is entitled to be a directory, too, isn't it? If so, why do we confirm its existence by checking if it is a regular file?

Guadalupe Gagnon

Level 37 , Tampa, United States

17 March, 14:03

Zip files only mimic directories but are regarded as files otherwise. I don't know how the validation code/tests are set up but I don't like that you have to use that method .isRegularFile(zipFile) to pass this task instead of exists() or notExists(). The only thing that I can theorize is that those last two methods have a warning in their descriptions that states: "Note that the result of this method is immediately outdated. If this method indicates the file exists then there is no guarantee that a subsequent access will succeed. Care should be taken when using this method in security sensitive applications."

Evgeniia Shabaeva

Level 41 , Budapest, Hungary

18 March, 10:07

I see. Thank you very much for the note.