Please help

Question about the task

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My extractAll method is on lines 81-105. I mostly copy-pasted the code for this method; several articles gave (more or less) the same code. I'm getting the mentor recommendation: CodeGym security exception. You are performing a forbidden or potentially dangerous operation.

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

13 April 2021, 15:26

useful

#1 you need to get the next zip entry every loop cycle. Otherwise line 89 is an infinite loop unless the first zipEntry is null. #2 I don't think ZipEntries return directories. For example: If I had a zip file containing 2 directories with 2 files contained in each directory(including just the base zip file directory), this is exactly what is returned for each call of getNextEntry() (i copied and pasted the direct result): result.txt RT6/2019PayrollSummary.pdf RT6/YTDMarch1st2020PayrollSummary.pdf test1.txt WHO/02-20.pdf WHO/02-21.pdf The results came in exactly like this, alphabetical. You can see there are no single directory results, just the files that are contained within. This means that line 91 in your code will always be false. You still have to create the directories, but the current code will not be able to handle that. *tips* you already have a copyData method. You can simply use that and replace lines 96-100. By writing different code that basically functions the same in multiple parts of your programs could introduce bugs that would be very hard to find.

Anthony Chalk

Level 30 , London, United Kingdom

13 April 2021, 19:41

public void extractAll(Path outputFolder) throws Exception{
     if (Files.notExists(zipFile))
         throw new NoSuchZipFileException();
     if (Files.notExists(outputFolder))
         Files.createDirectories(outputFolder);

     try (ZipInputStream zipInputStream = new ZipInputStream(Files.newInputStream(zipFile))){
         ZipEntry zipEntry = zipInputStream.getNextEntry();
         while (zipEntry != null){
             String filePath = outputFolder + File.separator + zipEntry.getName();
             File file = new File(zipEntry.getName());
             Path directory = new File(file.getParent()).toPath();
             if (Files.notExists(directory))
                 Files.createDirectories(directory);

             BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(filePath));
             copyData(zipInputStream, bos);

             zipEntry = zipInputStream.getNextEntry();
         }
     }
 }

This is my new code, it still fails the same conditions, but at least the security warning has gone

Guadalupe Gagnon

Level 37 , Tampa, United States

13 April 2021, 19:57

Im putting my thinking cap on.... give me a little bit of time to look over things

Guadalupe Gagnon

Level 37 , Tampa, United States

13 April 2021, 20:02

Path directory = new File(file.getParent()).toPath();

This line is incorrect. This is going to only be the path within the zip file, not the full qualified path. For example: if the zip file were located at "C:\users\myComp\desktop\temp\MyZip.zip" The zip entries from getNextEntry() would be: file1.foo folder1/file2.foo folder1/file3.foo etc So, that line is attempting to create a directory in the base drive (C:\ if windows). The correct place to create a directory would be in: (outputFolder + ZipEntry).getParent() *hint* the resolve() method of the Path class returns a new Path that is the result of combining the paths together with a String argument. This does what these lines attempt to do:

String filePath = outputFolder + File.separator + zipEntry.getName();
File file = new File(zipEntry.getName());
Path directory = new File(file.getParent()).toPath();

Guadalupe Gagnon

Level 37 , Tampa, United States

13 April 2021, 20:10

actually, while what I said above is true, i think the problem originates with this line:

File file = new File(zipEntry.getName());

Try passing 'filePath' to the new File instead of zipEntry.getName(). That should fix the issue.

Anthony Chalk

Level 30 , London, United Kingdom

14 April 2021, 08:11

I tried your second comment only and then tried this:

public void extractAll(Path outputFolder) throws Exception{
     if (Files.notExists(zipFile))
         throw new NoSuchZipFileException();
     if (Files.notExists(outputFolder))
         Files.createDirectories(outputFolder);

     try (ZipInputStream zipInputStream = new ZipInputStream(Files.newInputStream(zipFile))){
         ZipEntry zipEntry = zipInputStream.getNextEntry();
         while (zipEntry != null){
             String filePath = outputFolder + File.separator + zipEntry.getName();
             File file = new File(filePath);
             Path directory = new File(file.getParent()).toPath();
             if (Files.notExists(directory))
                 Files.createDirectories(outputFolder.resolve(directory));

             BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(filePath));
             copyData(zipInputStream, bos);

             zipEntry = zipInputStream.getNextEntry();
         }
     }
 }

the warning is now back lol