// i think this is from java-almanach .. haven't tested it
// http://javaalmanac.com/egs/java.io/CreateDir.html 
//

// Create a directory; all ancestor directories must exist
    boolean success = (new File("directoryName")).mkdir();
    if (!success) {
        // Directory creation failed
    }
    
    // Create a directory; all non-existent ancestor directories are
    // automatically created
    success = (new File("directoryName")).mkdirs();
    if (!success) {
        // Directory creation failed
    }