[roots]

Code:

		File file = new File("directory path");
		if(file.exists()){
			System.out.println("File Exists");
		}else{
			boolean wasDirecotyMade = file.mkdirs();
			if(wasDirecotyMade)System.out.println("Direcoty Created");
			else System.out.println("Sorry could not create directory");
		}

One more thing .. check java documentation for mkdir() and mkdirs() .. they are different and better if you could find that yourself...
hope it helps ..