opinion.java

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package ksnb;

import java.sql.*;
import java.util.*;
import java.io.*;
import javax.servlet.http.*;
import javax.servlet.*;
import java.text.*;

public class Opinion {
    private Connection con = null;
    private Statement stm = null;
    private ResultSet rs = null;
    private Collection ret = new ArrayList();
    private conn c = null;
    public Opinion() {
        //连接数据库
        try {
            c = new conn();
            con = c.getConncetion();
        } catch (Exception e) {
            System.out.println(e.toString());
        }

    }

    private static String convert(String str) {
        try {
            byte[] bytesStr = str.getBytes("ISO-8859-1");
            return new String(bytesStr, "gb2312");
        } catch (Exception ex) {
            return str;
        }
    }

    public Collection Query(HttpServletRequest request) {
        String sql = "select * from LeaveWord where [Level]=1 order by Date_time desc";
        //String sql="select * from LeaveWord";
        try {
            stm = con.createStatement();
            rs = stm.executeQuery(sql);
            String Content = null;
            String Author = null;
            String Answer = null;
            java.sql.Date date = null;
            while (rs.next()) {
                Content = rs.getString("Content");
                Author = rs.getString("Author");
                Answer = rs.getString("Answer");
                date = rs.getDate("Date_time");
                OpinionBean opinion = new OpinionBean();
                opinion.setContent(Content);
                opinion.setName(Author);
                opinion.setAnswer(Answer);
                opinion.setDate(date);
                ret.add(opinion);
            }
            rs.close();
            stm.close();
            request.setAttribute("o", ret);

        } catch (Exception e) {
            System.out.println(e);
        }
        return ret;
    }

    public void insert(HttpServletRequest request) {
        String sql =
                "insert into LeaveWord(Author,Content,Date_time) values(?,?,?)";
        //提取出从jsp页面中的值

        String name = convert(request.getParameter("username")); //未完成
        String content = convert(request.getParameter("content"));
        //从session中获取出用户是否登陆，对[level]进行赋值
        int i = 0;
        //java.sql.Date date=null;

        if (name == null)
            name = "过客";
        try {
            //写一个DATETIME对象
            DateFormat dateFormatter = DateFormat.getDateTimeInstance(
                    DateFormat.LONG, DateFormat.LONG);
            // 取得系统时间
            java.util.Date utilDate = new java.util.Date();
            // 转换成数据库时间
            java.sql.Date date = new java.sql.Date(utilDate.getTime());
            PreparedStatement stm = con.prepareStatement(sql);
            //设置插入语句中的参数

            stm.setString(1, name);
            stm.setString(2, content);
            stm.setDate(3, date);

            stm.executeUpdate();
            stm.close();
        } catch (Exception e) {
            System.out.println(e);
        }

    }

    public void pageination(HttpServletRequest request) {
        Connection sqlCon = null; //数据库连接对象
        Statement sqlStmt = null; //SQL语句对象
        ResultSet sqlRst = null; //结果集对象
        String strCon = null; //数据库连接字符串
        String strsql = null; //SQL语句
        int intPageSize; //一页显示的记录数
        int intRowCount = 0; //记录总数
        int intPageCount; //总页数
        int intPage; //待显示页码
        int i;
        intPageSize = 5;

        //System.out.println("Collection ok");
        //取得待显示页码
        //strsql="select Author,Content,Answer,Date_time from LeaveWord where [Level]=1";
        strsql = "select Author,Content,Answer,Date_time from LeaveWord where [Level]=1 order by Date_time desc";
        try {
            //连接数据库
            sqlCon = (new conn()).getConncetion();
            //创建一个可以滚动的只读的SQL语句对象
            sqlStmt = sqlCon.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                             ResultSet.CONCUR_READ_ONLY);
            //执行SQL语句并获取结果集
            sqlRst = sqlStmt.executeQuery(strsql);
            //获取记录总数
            //System.out.println("execute ok");
            request.setAttribute("pageination", sqlRst);
        } catch (Exception e) {
            System.out.println(e.toString());
        }
    }

}