方式一：

String startdate="2013-09-10";

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-mm-dd");

Date date=sdf.parse(startdate);

Calendar cld=Calendar.getInstance();

cld.setTime(date);

cld.add(Calendar.DATE, 1);

System.out.println(sdf.format(cld.getTime()));

===================================

public 
class 
$ {
 
    public 
static 
void 
main(String[] args) {
        Format f = new 
SimpleDateFormat("yyyy-MM-dd");
 
        Date today = new 
Date();
        System.out.println("今天是:" 
+ f.format(today));
 
        Calendar c = Calendar.getInstance();
        c.setTime(today);
        c.add(Calendar.DAY_OF_MONTH, 1);// 今天+1天
 
        Date tomorrow = c.getTime();
        System.out.println("明天是:" 
+ f.format(tomorrow));
    }
}
 
结果：
今天是:2013-10-09
明天是:2013-10-10
 

方式二：

String startdate="2013-09-10";

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-mm-dd");

Date date=null;

date = sdf.parse(startdate);

long t=date.getTime();

t+=24*60*60*1000;

date.setTime(t);

System.out.println(sdf.format(date));

 

方式三：

String startdate="2013-09-10";

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-mm-dd");

Date d = sdf.parse(startdate);

d.setDate(d.getDate() + 1);

startdate = sdf.format(d);

System.out.println(startdate);

 

增加一月

Date date = new Date();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");

Calendar calendar = Calendar.getInstance();

calendar.setTime(date);

calendar.add(Calendar.MONTH, 1);

System.out.println(sdf.format(calendar.getTime()));