Java日期格式處理

處理日期格式，運行main函數即可：

package testutil;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 * Created by wangpeng on 2018/2/26.
 */
public class DateFormat {

    public static void main(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        SimpleDateFormat sdf2 = new SimpleDateFormat("MM/dd/yyyy hh:mm:ss");
        Date date = new Date();
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.add(Calendar.DAY_OF_MONTH, -1);
        date = calendar.getTime();
        System.out.println(sdf.format(date));
        System.out.println(sdf1.format(date));
        System.out.println(sdf2.format(date));
    }
}