dateutil.java

这是一个关于电表的收费器的代码程序

package edu.njust.cs;
import java.sql.Timestamp;
import java.util.*;
public class DateUtil{	
	//由 xxxx-xx-xx 的格式,例如2005-01-23
	//转换为 Timestamp 格式		getTSFromYMD
	public static Timestamp getTSFromYMD(String s)	{	
		int year=Integer.parseInt(s.substring(0,4));
		int month=Integer.parseInt(s.substring(5,7));
		int day=Integer.parseInt(s.substring(8,10));
		GregorianCalendar gc=new GregorianCalendar(year,month-1,day,0,0,0);		
		return new Timestamp(gc.getTimeInMillis());
	}
	//由Timestamp转换为 xxxx-xx-xx 格式	
	public static String getYMDFromTS(Timestamp tp){	
		if(tp==null)	return "";
		GregorianCalendar gc=new GregorianCalendar();				
		gc.setTimeInMillis(tp.getTime());
		String m="";
		if((gc.get(Calendar.MONTH)+1)<10)
			m="0"+(gc.get(Calendar.MONTH)+1);
		else
			m=""+(gc.get(Calendar.MONTH)+1);
		String d="";
		if(gc.get(Calendar.DAY_OF_MONTH)<10)
			d="0"+gc.get(Calendar.DAY_OF_MONTH);
		else
			d=""+gc.get(Calendar.DAY_OF_MONTH);		
		return (gc.get(Calendar.YEAR))+"-"+m+"-"+d;
	}	
	//由GregorianCalendar
	//转换为 xxxx-xx-xx xx:xx:xx 格式	
	//例如 2005-01-29 13:23:24 
	public static String getYMDHMSFromGC(GregorianCalendar gc){
		if(gc==null)	return "";
		String yearMonthDay=getYMDFromTS(getTSFormGC(gc));
		String hour="";
		String minute="";
		String second="";
		if(gc.get(Calendar.HOUR_OF_DAY)<10)
			hour="0"+gc.get(Calendar.HOUR_OF_DAY);
		else
			hour=""+gc.get(Calendar.HOUR_OF_DAY);
		if(gc.get(Calendar.MINUTE)<10)
			minute="0"+gc.get(Calendar.MINUTE);
		else
			minute=""+gc.get(Calendar.MINUTE);
		if(gc.get(Calendar.SECOND)<10)
			second="0"+gc.get(Calendar.SECOND);
		else
			second=""+gc.get(Calendar.SECOND);			
		return ""+yearMonthDay+" "+hour+":"+minute+":"+second;
	}
	//由 xxxx-xx-xx xx:xx:xx 的格式转换为 Timestamp 格式
	public static Timestamp getTSFromYMDHMS(String s){	
		int year=Integer.parseInt(s.substring(0,4));
		int month=Integer.parseInt(s.substring(5,7));
		int day=Integer.parseInt(s.substring(8,10));	
		int hour=Integer.parseInt(s.substring(11,13));
		int minute=Integer.parseInt(s.substring(14,16));
		int second=Integer.parseInt(s.substring(17,19));		
		GregorianCalendar gc=new GregorianCalendar(year,month-1,day,hour,minute,second);		
		return new Timestamp(gc.getTimeInMillis());
	}	
	//从GregorianCalendar转换为Timestamp  的格式	
	public static Timestamp getTSFormGC(GregorianCalendar gc){
		return new Timestamp(gc.getTimeInMillis());
	}	
	//从Timestamp 转换为 GregorianCalendar的格式				
	public static GregorianCalendar getGCFromTS(Timestamp ts)	{
		GregorianCalendar gc=new GregorianCalendar();
		gc.setTimeInMillis(ts.getTime());
		return gc;
	}
	//判断是否为有效的时间格式
	//年(4位)-月(2位)-日(2位)      例如   2005-11-07 
	public static boolean isValidYMDFormat(String s){ 
		boolean flag=true;
		if(s.length()!=10)	return false;
		if(s.charAt(4)!='-'||s.charAt(7)!='-') flag=false;
		try{
			Integer.parseInt(s.substring(0,4));			
			Integer.parseInt(s.substring(5,7));
			Integer.parseInt(s.substring(8,10));
		}catch(NumberFormatException e){
			e.printStackTrace();
			flag=false;
		}			
		return flag;
	}
	//判断是否为有效的时间格式
	//年(4位)-月(2位)      例如   2005-11  
	public static boolean isValidYMFormat(String s)	{ 
			boolean flag=true;
			if(s.length()!=7)	 return false;
			if(s.charAt(4)!='-') flag=false;
			try{
				Integer.parseInt(s.substring(0,4));			
				Integer.parseInt(s.substring(5,7));
			}catch(NumberFormatException e){
				e.printStackTrace();
				flag=false;
			}			
			return flag;
		}
}