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Not sure if the problem is the way I've worded my condition, or the way I'm copying the data Relevant code is lines 116-146

It's time to remove something from an archive. An archive is a tricky thing—you can't just go and remove an element.
Why? Imagine we decided to invent our own text compression algorithm. After examining the source text, we see that the phrase "being a programmer is cool" occurs often. In the second and subsequent instances of our phrase, we can replace the phrase with a note that this location represents the same phrase that was used in line S, starting from character K and N characters long. As we replace a lot of repeated phrases, the text shrink noticeably, but becomes unreadable to those not familiar with our compression algorithm.
Of course, we can recover the text (extract it). Now imagine what we need to remove the part of the text that is referenced by the compressed fragments. If we did this, our entire archive would become meaningless. That's why you can't simply remove part of an archive. This is a highly simplified description of a compression technique; in reality, everything is far more complicated.
As a result, to remove something from an archive, you need to create a new archive, and copy over everything except the removed file. Then you replace the old archive with the newly created one.

1. Add a public void removeFiles(List<Path> pathList) throws Exception method to the ZipFileManager class. It will remove files from an archive. A list of the relative paths to the files inside the archive will be passed in pathList.
It must:
1.1. Throw a NoSuchZipFileException if the archive file doesn't exist.
1.2. Create a temporary archive file in the default directory using the Files class's createTempFile() method.
1.3. Go through all the files of the original archive, and check whether the current file is in the list for removal.
- If the file is in the list, display a message indicating that we have removed the corresponding file and move on to the next file.
- If the file is not in the removal list, copy it to the new archive
1.4. Replace the original archive file with the temporary file we wrote all of the required files to. You need to do this using the Files class's move() method
2. Add a public void removeFile(Path path) throws Exception method to the ZipFileManager class. It should call the removeFiles method, creating a list out of a single element. This can be done using the Collections class's singletonList() method. Look up how it works.
3. Implement the ZipRemoveCommand class's execute() method: create a ZipFileManager object, ask the user which file to remove from which archive, and call the removeFile() method.
Do everything else as we did in the other commands. You don't have to catch the PathNotFoundException, since the removeFile() method shouldn't throw it.
4. Run the program and verify that removing a file from an archive works.

Requirements:

You need to create a public void removeFiles(List<Path> pathList) throws Exception method in the ZipFileManager class.
The removeFiles method must throw a NoSuchZipFileException if the archive file doesn't exist.
The removeFiles method must create a temporary archive file using the Files.createTempFile method.
The removeFiles method should write all of the files from the old archive to the new archive, except those in the list for removal.
In the ZipFileManager class, you need to create a public void removeFile(Path path) throws Exception method that delegates the call to the removeFiles(List<Path> pathList) method.
The ZipRemoveCommand class's execute() method should get the ZipFileManager object and remove from the archive the file read from the console.

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

15 April 2021, 13:59

#1 you can't create a new outputstream for every file. You are going to want one Stream for the input (which you have) and one stream for the output. Make sure that it is a ZipOutputStream, which is the next point #2 In the code above, line 132, it is attempting to cast an OutputStream to a ZipOutputStream. This can not be done. Make sure that when you create the ZOS that you create a new one that wraps the OutputStream. tip: This one method is actually takes the extractAll() method and the addNewZipEntry() method and combines them together. Because you are filtering from one zip archive and then writing the results directly to another zip archive, you can't just use them. However, you can use the logic have already created by copy/paste and then modify it to satisfy the task requirements. One thing to pay attention to: In the addNewZipEntry method, see putNextEntry() and closeEntry().

Anthony Chalk

Level 30 , London, United Kingdom

15 April 2021, 14:21

public void removeFiles(List<Path> pathList) throws Exception{
     if (!Files.isRegularFile(zipFile)) {
         throw new NoSuchZipFileException();
     }

     Path tempArchive = Files.createTempFile("Temp Archive", null, null);

     try (ZipInputStream zipInputStream = new ZipInputStream(Files.newInputStream(zipFile))) {
         try (ZipOutputStream zipOutputStream = new ZipOutputStream(Files.newOutputStream(tempArchive))) {
             ZipEntry zipEntry = zipInputStream.getNextEntry();

             while (zipEntry != null) {
                 if (pathList.contains(Paths.get(zipEntry.getName()))) {
                     ConsoleHelper.writeMessage("We have removed the corresponding file");
                 } else {
                     zipOutputStream.putNextEntry(new ZipEntry(zipEntry.getName()));
                     copyData(zipInputStream, zipOutputStream);
                     zipOutputStream.closeEntry();
                 }
                 zipEntry = zipInputStream.getNextEntry();
             }
         }
     }
     Files.move(tempArchive, zipFile.getParent());
 }

It's still failing. Do I need to create the directories?

Guadalupe Gagnon

Level 37 , Tampa, United States

15 April 2021, 14:26

solution

Try: line 6: P tA = F.cTF(null,null); <- no name line 24: F.m(tA, zF, StandardCopyOption.REPLACE_EXISTING); <- no .getParent()

Guadalupe Gagnon

Level 37 , Tampa, United States

15 April 2021, 14:28

I think the default behavior is REPLACE_EXISTING, though im not 100% sure. No harm to make sure to include it for readabillity though.

Anthony Chalk

Level 30 , London, United Kingdom

15 April 2021, 15:05

Thank you, saw on Oracle that there were different options for the 3rd argument, including REPLACE_ALL, but I couldn't find the correct syntax for passing the argument

Guadalupe Gagnon

Level 37 , Tampa, United States

15 April 2021, 15:09

Practice makes perfect. Good job solving.

Anthony Chalk

Level 30 , London, United Kingdom

15 April 2021, 15:29

Thank you, think I'm starting to get the hang of it