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Method works well even with inner directories but not passes the validation. Is it completable?

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.command.ExitCommand; import com.codegym.task.task31.task3110.exception.NoSuchZipFileException; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.nio.file.Path; import java.nio.file.Paths; public class Archiver { public static void main(String[] args) throws Exception { Operation operation = null; while (operation != Operation.EXIT) { 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."); } } } public static Operation askOperation() throws IOException{ ConsoleHelper.writeMessage("Select an operation:"); for (Operation item : Operation.values()) { ConsoleHelper.writeMessage(item.ordinal() + " - " + item.name().toLowerCase()); } return Operation.values()[ConsoleHelper.readInt()]; } }

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Roman

Level 41

18 April 2019, 12:02

solution

Did you test unzip functionality? I did and received wrong results: The size of the original file is 4 bytes The size of the unzipped file is 5 bytes The content of the original file is:

test

The content of the unzipped file is:

testÿ

Oleh

Level 32 , Kyiv, Ukraine

18 April 2019, 14:09

useful

Sorry for the fake alert. I tested unzip on the exe files, couldn't even think there is some extra symbol at the end of the text files. The problem was in the copyData method. It has passed validation already 5 tasks ago so I didn't test it again. P.S. Sometimes some classes with prepared code appear in the package with "another" name. Is this code supposed to replace my own? Or I shouldn't see this prepared code at all and it's a bug? So copyData was in this package but I didn't replace it.

private void copyData(InputStream in, OutputStream out) throws Exception {
    byte[] buffer = new byte[8 * 1024];
    int len;
    while ((len = in.read(buffer)) > 0) {
        out.write(buffer, 0, len);
    }
}