How to Programmatically Change File Permissions

How do I programmatically change file permissions?

Full control over file attributes is available in Java 7, as part of the "new" New IO facility (NIO.2). For example, POSIX permissions can be set on an existing file with setPosixFilePermissions(), or atomically at file creation with methods like createFile() or newByteChannel().

You can create a set of permissions using EnumSet.of(), but the helper method PosixFilePermissions.fromString() will uses a conventional format that will be more readable to many developers. For APIs that accept a FileAttribute, you can wrap the set of permissions with with PosixFilePermissions.asFileAttribute().

Set<PosixFilePermission> ownerWritable = PosixFilePermissions.fromString("rw-r--r--");
FileAttribute<?> permissions = PosixFilePermissions.asFileAttribute(ownerWritable);
Files.createFile(path, permissions);

In earlier versions of Java, using native code of your own, or exec-ing command-line utilities are common approaches.

java- How do programmatically change user to root before changing file permissions?

There is no way to change the owner of a running process (be it a JVM or anything else).

You can however spawn a new, privileged process to do the "dirty" work.

How do I programmatically change file permissions?

Full control over file attributes is available in Java 7, as part of the "new" New IO facility (NIO.2). For example, POSIX permissions can be set on an existing file with setPosixFilePermissions(), or atomically at file creation with methods like createFile() or newByteChannel().

You can create a set of permissions using EnumSet.of(), but the helper method PosixFilePermissions.fromString() will uses a conventional format that will be more readable to many developers. For APIs that accept a FileAttribute, you can wrap the set of permissions with with PosixFilePermissions.asFileAttribute().

Set<PosixFilePermission> ownerWritable = PosixFilePermissions.fromString("rw-r--r--");
FileAttribute<?> permissions = PosixFilePermissions.asFileAttribute(ownerWritable);
Files.createFile(path, permissions);

In earlier versions of Java, using native code of your own, or exec-ing command-line utilities are common approaches.

set execute permition on file

JAVA5 and prior there is workaround using exec extracted from here:

public static void runCmd (String[] cmd) {

    try {
        Process p = Runtime.getRuntime().exec(cmd);
        BufferedReader r = new BufferedReader(
            new InputStreamReader (
                p.getInputStream()
            )
        );
    } catch(Exception e) {
    }
}

USE

runCmd(new String[] {
    "/bin/chmod",
    "755",
    "/path/to/your/script"
});

By terminal in Linux

UP TO JAVA6

For permissions use File::setExecutable(boolean [, boolean])

File file = new File("/your/path/to/file/file_script.sh");
file.setExecutable(true);

Check this MKYONG permissions tutorial

Set File Permissions in C#

Take a look at File.SetAttributes(). There are lots of examples online about how to use it.

Taken from that MSDN page:

FileAttributes attributes = File.GetAttributes(path);

        if ((attributes & FileAttributes.Hidden) == FileAttributes.Hidden)
        {
            // Show the file.
            attributes = RemoveAttribute(attributes, FileAttributes.Hidden);
            File.SetAttributes(path, attributes);
            Console.WriteLine("The {0} file is no longer hidden.", path);
        } 
        else 
        {
            // Hide the file.
            File.SetAttributes(path, File.GetAttributes(path) | FileAttributes.Hidden);
            Console.WriteLine("The {0} file is now hidden.", path);
        }

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