1 import java.text.ParseException; 2 import java.text.SimpleDateFormat; 3 import java.util.Calendar; 4 import java.util.Date; 5  6  7 public class TestMinusOneMonth { 8  9     public static void main(String[] args) {10         String string = "2014-01-01";11         SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");12         try {13             Date date = sdf.parse(string);14             Calendar calendar = Calendar.getInstance();15             calendar.setTime(date);16             calendar.add(Calendar.MONTH, -1);17             date = calendar.getTime();18             string = sdf.format(date);19             System.out.println(string); //2013-12-0120         } catch (ParseException e) {21             e.printStackTrace();22         }23     }24 }