Get a list of all the files in a directory (recursive)

I'm trying to get (not print, that's easy) the list of files in a directory and its sub directories.

I've tried:

def folder = "C:\\DevEnv\\Projects\\Generic";
def baseDir = new File(folder);
files = baseDir.listFiles();

I only get the directories. I've also tried:

def files = [];

def processFileClosure = {
        println "working on ${it.canonicalPath}: "
        files.add (it.canonicalPath);
    }

baseDir.eachFileRecurse(FileType.FILES, processFileClosure);

But "files" is not recognized in the scope of the closure.

How do I get the list?

This code works for me:

import groovy.io.FileType

def list = []

def dir = new File("path_to_parent_dir")
dir.eachFileRecurse (FileType.FILES) { file ->
  list << file
}

Afterwards the list variable contains all files (java.io.File) of the given directory and its subdirectories:

list.each {
  println it.path
}

Newer versions of Groovy (1.7.2+) offer a JDK extension to more easily traverse over files in a directory, for example:

import static groovy.io.FileType.FILES
def dir = new File(".");
def files = [];
dir.traverse(type: FILES, maxDepth: 0) { files.add(it) };

See also [1] for more examples.

[1] http://mrhaki.blogspot.nl/2010/04/groovy-goodness-traversing-directory.html

The following works for me in Gradle / Groovy for build.gradle for an Android project, without having to import groovy.io.FileType (NOTE: Does not recurse subdirectories, but when I found this solution I no longer cared about recursion, so you may not either):

FileCollection proGuardFileCollection = files { file('./proguard').listFiles() }
proGuardFileCollection.each {
    println "Proguard file located and processed: " + it
}