calendar

自己很少写博客，现在学着慢慢总结所学的知识：
这是利用calendar所写的小程序
public class TimeData {

public static String getNowTime(){
Calendar c=new GregorianCalendar();
        StringBuffer sb=new StringBuffer();
        sb.append(c.get(Calendar.YEAR)).append("-").append(c.get(Calendar.MONTH)+1).append("-").append(c.get(Calendar.DAY_OF_MONTH));
       
return sb.toString();
}
public static String getNextMonth(int offset){
Calendar c=new GregorianCalendar();
c.roll(Calendar.DAY_OF_MONTH, offset);
int i=c.get(Calendar.DAY_OF_MONTH);
if(i<offset){
c.roll(Calendar.MONTH, 1);
}
        StringBuffer sb=new StringBuffer();
        sb.append(c.get(Calendar.YEAR)).append("-").append(c.get(Calendar.MONTH)+1).append("-").append(c.get(Calendar.DAY_OF_MONTH));
       
return sb.toString();
}
public static String getLastMonth(int offset){
Calendar c=new GregorianCalendar();
int i=c.get(Calendar.DAY_OF_MONTH)-offset;
if(i<0)
c.roll(Calendar.MONTH, -1);
        c.roll(Calendar.DAY_OF_MONTH, -offset);
    StringBuffer sb=new StringBuffer();
            sb.append(c.get(Calendar.YEAR)).append("-").append(c.get(Calendar.MONDAY)+1).append("-").append(c.get(Calendar.DAY_OF_MONTH)); 
return sb.toString();
}

   public static boolean compareToDay(Calendar start,Calendar end,String str){
String[] date = str.split("/");
Calendar temp = Calendar.getInstance();
try {
temp.set(Calendar.YEAR, Integer.valueOf(date[0]));
temp.set(Calendar.MONTH, Integer.valueOf(date[1])-1);
temp.set(Calendar.DAY_OF_MONTH, Integer.valueOf(date[2]));
} catch (Exception e) {
return false;
}

if(temp.compareTo(start)>-1&&temp.compareTo(end)<1){
return true;
}
   return false;   
  
   }