java-计算当前时间的前5天前的日期

	   SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");                
	  
	    Calendar c = Calendar.getInstance();           
	  
	    c.add(Calendar.DATE, - 5);           
	  
	    Date time = c.getTime();         
	  
	    String preDay = sdf.format(time); 
	    
	    System.out.println(preDay);