Let's start by creating a file and adding some content to it. Open your shell, start groovysh and type the following code:

f = new File('test.txt')
f << 'hello, this is a test file'

You should now see a file named test.txt in the same directory where you started groovysh.

On a DOS console, type:

attrib test.txt

The output should be as follows:

A       I    C:hello.txt

The initial on the left stands for the first letter of the enabled attribute: A for "archive", S for "system", H for "hidden" and R for "read-only".

With the exclusion of the read-only attribute; in Java, there is no way to set the Windows file attributes through the File API. To make a file read-only:

f.setReadOnly()

This will change the R attribute:

attrib test.txt
A    R  I    C:hello.txt

Groovy provides a simple way to execute command line processes. Simply write the command line as a string and call the execute method. The execute method returns a java.lang.Process instance, which will subsequently allow the in/err/outstreams to be processed and the exit value from the process to be inspected.

This snippet executed from groovish will output the directory listing on a UNIX machine:

println 'ls -al'.execute().text

Alternatively, we can access the stream resulting from the process and print the result line-by-line:

p = 'ls -al'.execute().text
p.in.eachLine { line -> print line }

If you run Groovy using JDK 7, you can leverage the new NIO API to set the Windows file attributes. The following example shows you how to do it:

import java.nio.file.*
import java.nio.file.attribute.*
def f = new File('hello.txt')
f << 'hello, hello'
def path = Paths.get('C:\groovybook\hello.txt')
def dosView = Files.getFileAttributeView(
                path, DosFileAttributeView
              )
dosView.hidden = true
dosView.archive = true
dosView.system = true

This code will fail if it is executed in an environment other than Windows.