My Question On Calendar and Date

Question

Hi, I am making a query to a table: T_HR_CONTRACT,
which stores the labor contract of a company.
END_DATE is a field of table T_HR_CONTRACT. Its type is date.
Now, I need to search the contract end in each month.
select * from T_HR_CONTRACT where fEND_DATE >= theStartDayOfCurrenctMonth and fEND_DATE < theStartDayOfNextMonth;
or
select * from T_HR_CONTRACT where fEND_DATE >= theStartDayOfCurrenctMonth and fEND_DATE <= theLastDayOfCurrenctMonth;
How can I utilize the java class Calendar or Date to get
the first day of current month,
the last day of current month,
the first day of next month?
I am new to Calendar and Date class. Please give me some help!

Answer 1

Ok, I have solve the problem as following:
//get the first day of this month, by using StringBuffer, we can enhance
//the effiency
StringBuffer today = new StringBuffer();
Calendar rightNow = Calendar.getInstance();
today.append(rightNow.get(rightNow.YEAR));
today.append("-");
today.append((rightNow.get(rightNow.MONTH) + 1));
today.append("-01");
String todayDate = today.toString();
//get the first day of next month
StringBuffer next = new StringBuffer();
//if the month is December, then get the first day of next year!
if(rightNow.get(rightNow.MONTH) == 11)
next.append(rightNow.get(rightNow.YEAR) + 1);
next.append("-01-01");
else
next.append(rightNow.get(rightNow.YEAR));
next.append("-");
next.append(rightNow.get(rightNow.MONTH) + 2);
next.append("-01");
String nextDate = next.toString();