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import java.io.File;

public class Main {
    public static void main(String[] argv) throws Exception {
        // Delete the 'test' directory in the current directory
        deleteDir(new File("./test"));
    }
    public static boolean deleteDir(File dir) {
        if (dir.isDirectory()) {
            String[] children = dir.list();
            for (int i = 0; i < children.length; i++) {
                boolean success = deleteDir(new File(dir, children[i]));
                if (!success) {
                    return false;
                }
            }
        }
        if (dir.delete()) {
            System.out.println("Directory has been deleted!");
            return true;
        } else {
            System.out.println("Failed to delete the directory!");
            return false;
        }
    }
}

Directory has been deleted!