birthcontroller.java

java servlet 一些简单练习

package train.jsp;

import java.io.IOException;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class BirthController extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		String year = request.getParameter("year");
		String month = request.getParameter("month");
		String day = request.getParameter("day");

		int liveDays = 0;
		int leftDays = 0;
		try {
			liveDays = liveDays(year, month, day);
		} catch (NumberFormatException e) {
			request.getRequestDispatcher("/birth/error.html").forward(request,
					response);
			return;
		}
		leftDays = 365 * 100 - liveDays;
		request.setAttribute("liveDays", liveDays);
		request.setAttribute("leftDays", leftDays);
		request.getRequestDispatcher("/birth/liveDays.jsp").forward(request,
				response);
	}

	private int liveDays(String yearStr, String monthStr, String dayStr)
			throws NumberFormatException {
		int year = Integer.parseInt(yearStr);
		int month = Integer.parseInt(monthStr);
		int day = Integer.parseInt(dayStr);
		if (year < 1900 || year > 2009 || month < 1 || month > 12 || day < 1
				|| day > 31)
			throw new NumberFormatException();
		GregorianCalendar c = new GregorianCalendar(year, month - 1, day);

		long liveMillSeconds = (new Date().getTime() - c.getTime().getTime());
		long liveDays = liveMillSeconds / (1000 * 60 * 60 * 24);
		return (int)liveDays;
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doGet(request, response);
	}

}