IOException - Access Denied Using FileOutputStream

Question

I get the following IOException :

java.io.IOException: Access is denied
 at java.io.WinNTFileSystem.createFileExclusively(Native Method)
 at java.io.File.cre         


        

Answer 1

The issue is that these calls step on each other:

  fileToWrite.mkdirs(); //creates a directory e.g. C:\temp\foo\x
  fileToWrite.createNewFile(); //attempts to create a file C:\temp\foo\x

The create operation fails because you just created a directory with the same name than the file you want to create.

What you want to do instead is:

fileToWrite.getParentFile().mkdirs()

And also, the call to createNewFile() is unnecessary.

Based on your code. The following "unzips" a zip file:

import java.io.*;
import java.util.zip.ZipFile;
import java.util.zip.ZipEntry;
import java.util.Enumeration;

public class Unzipper {
    public static void main(String[] args)
            throws IOException {
        final File file = new File(args[0]);
        final ZipFile zipFile = new ZipFile(file);
        final byte[] buffer = new byte[2048];
        final File tmpDir = new File(System.getProperty("java.io.tmpdir"), zipFile.getName());

        if(!tmpDir.mkdir() && tmpDir.exists()) {
            System.err.println("Cannot create: " + tmpDir);
            System.exit(0);
        }

        for(final Enumeration entries = zipFile.entries(); entries.hasMoreElements();) {
            final ZipEntry zipEntry = (ZipEntry) entries.nextElement();
            System.out.println("Unzipping: " + zipEntry.getName());

            final InputStream is = zipFile.getInputStream(zipEntry);
            final File fileToWrite = new File(tmpDir, zipEntry.getName());
            final File folder = fileToWrite.getParentFile();
            if(!folder.mkdirs() && !folder.exists()) {
                System.err.println("Cannot create: " + folder);
                System.exit(0);
            }

            if(!zipEntry.isDirectory()) {
                //No need to use buffered streams since we're doing our own buffering
                final FileOutputStream fos = new FileOutputStream(fileToWrite);
                int size;
                while ((size = is.read(buffer)) != -1) {
                    fos.write(buffer, 0, size);
                }
                fos.close();
                is.close();
            }
        }
        zipFile.close();
    }
}

Disclaimer: I haven't tested it beyond the very basics.

Answer 2

It also could be that in context where you are launching the application you haven't access rights to the place where you are trying to create the file. Launch the app as admin or create the file in the project folder.

Answer 3

Why are you calling createNewFile()? Just create the FileOutputStream.