mainlistservlet.java

一个oracle和JSP做的论坛

package hcit.Servlet;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.sql.*;
import hcit.common.*;

public class mainlistServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GBK";

    //Initialize global variables
    public void init() throws ServletException {
    }

    //Process the HTTP Get request
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        response.setContentType(CONTENT_TYPE);
        PrintWriter out = response.getWriter();

        HttpSession session = request.getSession();
        String order = request.getParameter("orderby");

        Oraclejoin oj = new Oraclejoin(); //创建分页类对象
        DBConnect db = new DBConnect();
        ResultSet rs = null;

        ArrayList list = new ArrayList();

        String sql = "select * from maintopic "; //形成查询条件
        String cur_page; //设置主帖表的分页变量
        String m_total_page; //设定总页数变量
        String m_total_record; //设定总记录数变量

        cur_page = request.getParameter("cur_page"); //从请求中读取当前页号

        if (cur_page == null) { //如果为空，说明是第一页!!!!!!!
            cur_page = "1";
        }

        oj.setOrderby(order);
        oj.setSql(sql);
        oj.setP_curpage(Integer.parseInt(cur_page));
        rs = oj.getPage(); //得到当前页的记录集

        m_total_page = oj.getTotalPage();
        m_total_record = oj.getTotalRecord();

        if (Integer.parseInt(cur_page) >= Integer.parseInt(m_total_page)) { //设定翻页上下限：下限为1，上限为m_total_page
            cur_page = m_total_page;
        }
        if (Integer.parseInt(cur_page) <= 1) {
            cur_page = "1";
        }

        session.setAttribute("cur_page", cur_page); //将当前页号存入会话中
        try {
            while (rs.next()) { //利用循环，将记录集中的数据存入ArrayList对象中
                MainTopic_Pojo mpojo = new MainTopic_Pojo(); //创建主帖表的简单值对象
                mpojo.setM_topicid(rs.getString("M_TOPICID"));
                mpojo.setTopic(rs.getString("TOPICTITLE"));
                mpojo.setContent(rs.getString("content"));
                mpojo.setUserid(rs.getString("USERID"));
                mpojo.setP_num(Integer.parseInt(rs.getString(
                        "p_num")));
                mpojo.setR_num(Integer.parseInt(rs.getString(
                        "r_num")));
                mpojo.setC_date(rs.getDate("C_DATE"));
                mpojo.setTopictitle(rs.getString("Topictitle"));
                list.add(mpojo);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
        session.setAttribute("m_total_page", m_total_page);
        session.setAttribute("m_total_page", m_total_page);
        session.setAttribute("m_total_record", m_total_record);
        session.setAttribute("m_list", list); //将得到的当前页的list存入会话中

        RequestDispatcher rd = request.getRequestDispatcher("main.jsp");
        rd.forward(request, response);

    }


    //Process the HTTP Post request
    public void doPost(HttpServletRequest request,
                       HttpServletResponse response) throws
            ServletException, IOException {
        doGet(request, response);
    }

    //Clean up resources
    public void destroy() {
    }
}