homepageservlet.java

用java编写的网页基于Ajax的应用

package book.servlet;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.*;

import book.portal.table.LayoutEO;
import book.portal.table.UserEO;
import book.portal.*;

public class HomepageServlet extends HttpServlet {
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, java.io.IOException {
		boolean bSuccess = true;
		UserEO user = null;
		LayoutEO layout = null;
		HttpSession session = ((HttpServletRequest) request).getSession(true);//获得session
		String userId = (String) session.getAttribute("user");//获得session中user的值
		if (userId == null || userId.equals("")) {//如果user的值不存在
			bSuccess = false;
			RequestDispatcher dispatcher = request.getRequestDispatcher("login.jsp");//返回login.jsp页面
			dispatcher.forward(request, response);
		} else {//如果user的值存在
			user = new UserEO(Integer.parseInt(userId));//创建UserEO对象
			layout = LayoutEO.getInstance(user);//获得该User的布局设置
		}
		String action = request.getParameter("action");//获得action的值
		if (bSuccess && action != null && action.equals("close")) {//如果等于close,删除该窗口
			String id = request.getParameter("id");
			String side = request.getParameter("side");
			if (side != null && side.equals("right")) {
				String s = layout.getColNarrowRight();
				layout.setColNarrowright(Util.replaceAWithB(s, id + ",", ""));
			} else if (side != null && side.equals("left")) {
				String s = layout.getColNarrowLeft();
				layout.setColNarrowLeft(Util.replaceAWithB(s, "," + id, ""));

			} else if (side != null && side.equals("wide"))
			{
				String s = layout.getColWide();
				layout.setColWide(Util.replaceAWithB(s, ","+ id, ""));
			}
			bSuccess = layout.ToDb();
		}else if (bSuccess && action != null && action.equals("change"))//如果等于change,重新保存布局
		{
			String left = request.getParameter("left");//获得左侧布局
			String wide = request.getParameter("wide");//获得中间布局
			String right = request.getParameter("right");//获得右侧布局
			layout.setColNarrowLeft(left);
			layout.setColWide(wide);
			layout.setColNarrowright(right);
			bSuccess = layout.ToDb();//更新数据库
		}
	}

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

		doPost(request, response);
	}

}