reloanbookservlet.java

图书馆管理系统！利用java的mvc开发！

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package cn.edu.jmu.jc;

import cn.edu.jmu.beans.LoanRecord;
import cn.edu.jmu.util.MysqlUtil;
import java.io.IOException;
import java.text.Format;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.dbutils.handlers.BeanListHandler;

/**
 *
 * @author jiangchen
 */
public class reloanBookServlet extends HttpServlet {

    /** 
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");        
        request.setCharacterEncoding("UTF-8");
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet 方法。单击左侧的 + 号以编辑代码。">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
        if (request.getHeader("referer") == null) {
            response.sendRedirect("index.jsp");
        } else {
            doPost(request, response);
        }
    }

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
        String message = "";
        int state = 0;
        String brid = request.getParameter("brid");
        String bid = request.getParameter("bid");
        MysqlUtil db = new MysqlUtil("java:/comp/env/jdbc/mysql");
        db.init();
        String sql = "select lid,brid,bid,brDate,reloanDateNum,lastBackDate" +
                " from loan where brid=? and bid=?";
        if (bid.equals("")) {
            message = "对不起，书的登录号不能为空，请您重新输入！";
            state = 1;
        } else {
            String[] param1 = {brid, bid};
            List result = (List) db.query(sql, param1, new BeanListHandler(LoanRecord.class));
            if (result.size() == 0) {
                message = "对不起，该借阅者并未借阅该书，请您重新输入！";
                state = 1;
            } else {
                LoanRecord loanRecord = (LoanRecord) result.get(0);
                int reloanDateNum = loanRecord.getReloanDateNum();
                if (reloanDateNum == 0) {
                    message = "对不起，该书已续满！";
                    state = 1;
                } else {
                    Calendar lastBackDateCalender = Calendar.getInstance();
                    lastBackDateCalender.setTime(loanRecord.getLastBackDate());
                    lastBackDateCalender.add(Calendar.DAY_OF_MONTH, reloanDateNum);
                    Format format = new SimpleDateFormat("yyyy-MM-dd");
                    Date lastBackDateDate = lastBackDateCalender.getTime();
                    String lastBackDate = format.format(lastBackDateDate);

                    sql = "update loan set reloanDateNum=?,lastBackDate=? where brid=? and bid=?";
                    Object[] param2 = {0, lastBackDate, brid, bid};
                    db.update(sql, param2);
                    message = "操作成功！";
                }
            }
        }
        if (state == 0) {
            String hyperlink = "<a href=\"librarianManage.jsp\">返回</a></br>" +
                    "<form action=\"/libraryMIS/dispalyReloanBookInterface\" method=\"post\" name=\"form1\" id=\"form1\">" +
                    "<table align=\"center\"><tr>" +
                    "<td><input type=\"hidden\" name=\"brid\" value=\"" + brid +
                    "\"/></td><td><input type=\"submit\" name=\"Submit1\" value=\"继续续借\"/></td>" +
                    "</tr></table></form>";
            request.setAttribute("title", "操作成功！");
            request.setAttribute("message", message);
            request.setAttribute("hyperlink", hyperlink);
            request.getRequestDispatcher("/result.jsp").forward(request, response);
        } else {
            String hyperlink = "<input type=button value=\"返回\" onClick=\"history.back(-1)\">";
            request.setAttribute("title", "操作失败！");
            request.setAttribute("message", message);
            request.setAttribute("hyperlink", hyperlink);
            request.getRequestDispatcher("/result.jsp").forward(request, response);
        }
    }

    /** 
     * Returns a short description of the servlet.
     */
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}