java 时间大小的比较

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

public class A {
public static void main(String[] args) throws ParseException{
Date d1 = Calendar.getInstance().getTime();
String s1 = new SimpleDateFormat("yyyy"+"-"+"MM"+"-"+"dd HH" + ":" + "mm" + ":" + "ss").format(d1);
System.out.println("s1==="+s1);

String time = "2011-08-13 14:42:43";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date dd= sdf.parse(time.toString());
String ss = new SimpleDateFormat("yyyy"+"-"+"MM"+"-"+"dd HH" + ":" + "mm" + ":" + "ss").format(dd);
System.out.println("ss==="+ss);

int i = d1.compareTo(dd);
if(i<0){
System.out.println("d1更早");
}else if(i==0){
System.out.println("d1一样");
}else{
System.out.println("dd更早");
}

}
}