Java IO & NIO - Files.setOwner() Examples

package com.logicbig.example.files;

import java.io.IOException;
import java.nio.file.FileSystem;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.attribute.UserPrincipal;
import java.nio.file.attribute.UserPrincipalLookupService;

/**
 * In windows, before running this example,
 * you can change the owner of a file using following command
 * (must run as admin).
 * icacls "C:\temp\trish-file.txt" /setowner "trish" /T /C
 * Given that current logged in user is "joe"
 */
public class SetOwnerExample {

    public static void main(String... args) throws IOException {
        Path path = Paths.get("C:\\temp\\trish-file.txt");
        System.out.println("File: " + path);
        System.out.println("Exists: " + Files.exists(path));
        System.out.println("-- owner before --");
        UserPrincipal owner = Files.getOwner(path);
        System.out.println("Owner: " + owner);

        System.out.println("-- lookup other user --");
        FileSystem fileSystem = path.getFileSystem();
        UserPrincipalLookupService service = fileSystem.getUserPrincipalLookupService();
        UserPrincipal userPrincipal = service.lookupPrincipalByName("joe");
        System.out.println("Found UserPrincipal: " + userPrincipal);

        //changing owner
        Files.setOwner(path, userPrincipal);

        System.out.println("-- owner after --");
        owner = Files.getOwner(path);
        System.out.println("Owner: " + owner.getName());
    }
}