date one month back

DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
java.util.Date date = new java.util.Date();
String datetime= dateFormat.format(date);

like this i get current date. How i can get date one months back?

regards

Code:

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DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
Date date = new Date();
System.out.println("date = " + dateFormat.format(date));
// get date one months back
Calendar calendar = Calendar.getInstance();
System.out.println("current calendar time = " +
                    dateFormat.format(calendar.getTime()));
calendar.add(Calendar.MONTH, -1);
System.out.println("calendar one month back = " +
                    dateFormat.format(calendar.getTime()));

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