昨天:

SimpleDateFormat sdf=new SimpleDateFormat("yyyMMdd");
    	Calendar calendar = new GregorianCalendar();
    	calendar.setTime(new Date());
    	calendar.add(calendar.DATE,-1);
    	String date= sdf.format(calendar.getTime());
    	System.out.println("【定时】当前时间:"+date);

今天:

Date d=new Date();
    	SimpleDateFormat sdf=new SimpleDateFormat("yyyMMdd");
    	String date=sdf.format(d);

明天:

SimpleDateFormat sdf=new SimpleDateFormat("yyyMMdd");
    	Calendar calendar = new GregorianCalendar();
    	calendar.setTime(new Date());
    	calendar.add(calendar.DATE,1);
    	String date= sdf.format(calendar.getTime());
    	System.out.println("【定时】当前时间:"+date);

 

或者 昨天

Date date4 = new Date(new Date().getTime()-24*60*60*1000);
String time = sdf.format(date4);
System.out.println(time);