java中怎么把日期格式化

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

public class test{

    public static void main(String args[]) {
        Date newTime = new Date();
        //设置时间格式
        SimpleDateFormat sdf1 = new SimpleDateFormat("y-M-d h:m:s a E");
        SimpleDateFormat sdf2 = new SimpleDateFormat("yy-MM-dd hh:mm:ss a E");
        SimpleDateFormat sdf3 = new SimpleDateFormat("yyyy-MMM-ddd hhh:mmm:sss a E");
        SimpleDateFormat sdf4 = new SimpleDateFormat("yyyyy-MMMM-dddd hhhh:mmmm:ssss a E");
        
        //获取的时间，是本机的时间
        String formatDate1 = sdf1.format(newTime);
        String formatDate2 = sdf2.format(newTime);
        String formatDate3 = sdf3.format(newTime);
        String formatDate4 = sdf4.format(newTime);

        System.out.println(formatDate1);  
        System.out.println(formatDate2); 
        System.out.println(formatDate3); 
        System.out.println(formatDate4); 
    }
}