guestbook.java

jsp开发常用信息管理系统适合初学者学习 jsp开发常用信息管理系统适合初学者学习

package ch08;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Date;
/**
 * @author <a href="[e-mail]">Cheng Wei</a>
 *	留言本的管理类
 */
public class Guestbook {
    //数据库连接
    private Connection conn;

    //错误
    public String error;

    //留言本标题
    private String title;

    //每页显示留言条数
    private int pageshownumber;

    //留言总数
    private int mes_total;

    //分页总数
    private int page_total;

    //当前页面
    private int currentpage;

    //管理员用户
    private String adm_user;

    //管理员密码
    private String adm_psw;

    /**
     * 留言本的构造类 系统初始化后设置整个系统中需要的各个参数变量
     */
    public Guestbook() {
        conn = null;
        error = null;
        title = null;
        pageshownumber = 15;
        mes_total = 0;
        page_total = 0;
        currentpage = 1;
        adm_user = null;
        adm_psw = null;
    }

    /**
     * 系统初始化，完成数据库连接
     * 
     * @param driver	驱动
     * @param mysqlUrl	路径
     * @param user 		用户
     * @param password	密码
     * @return
     */
    public boolean init(String driver, String mysqlUrl, String user,
            String password) {
        try {
            Class.forName(driver);
            conn = DriverManager.getConnection(mysqlUrl, user, password);
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 系统初始化，完成数据库连接
     * 
     * @param driver
     * @param mysqlUrl
     * @param user
     * @param password
     * @return
     */
    public boolean init2(String driver, String mysqlUrl, String user,
            String password) {
        try {
            Class.forName(driver);
            String dburl = mysqlUrl + "?user=" + user + "&password=" + password
                    + "&useUnicode=true&characterEncoding=GBK";
            conn = DriverManager.getConnection(dburl);
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 字符串编码转换成GBK
     * 
     * @param str		需要转码的字符串      
     * @return 转码后的字符串
     */
    public String getStr(String str) {
        String s2;
        String s1 = str;

        try {
            byte abyte0[] = s1.getBytes("GBK");
            s2 = new String(abyte0);
            return s2;
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return null;
    }

    /**
     * 处理HTML中的特殊字符
     * @param str
     * @return
     */
    public String HtmlSpecialChars(String str) {
        if (str == null || str.equals(""))
            return str;
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < str.length(); i++)
            if (str.charAt(i) == '\n')
                sb = sb.append("<br>");
            else if (str.charAt(i) == ' ')
                sb = sb.append("&nbsp;");
            else if (str.charAt(i) == '<')
                sb = sb.append("&lt;");
            else if (str.charAt(i) == '>')
                sb = sb.append("&gt;");
            else
                sb = sb.append(str.substring(i, i + 1));

        String newstr = sb.toString();
        return newstr;
    }

    /**
     * 发表文章
     * @param as
     * @return
     */
    public boolean post(String info[]) {
        String name;
        String qq;
        String email;
        String homepage;
        String headima;
        String word;
        long l;
        name = info[0];
        qq = info[1];
        email = info[2];
        homepage = info[3];
        headima = info[4];
        word = info[5];
        if (qq == "" || qq == null || qq.equals(""))
            qq = "no";
        if (email == "" || email == null || email.equals(""))
            email = "no";
        if (homepage == "" || homepage == null || homepage.equals(""))
            homepage = "no";
        Date date = new Date();
        l = date.getTime();
        PreparedStatement preparedstatement;
        try {
            preparedstatement = conn
                    .prepareStatement("insert into `guestbook` values('',?,?,?,?,?,?,?)");
            preparedstatement.setString(1, name);
            preparedstatement.setString(2, qq);
            preparedstatement.setString(3, email);
            preparedstatement.setString(4, homepage);
            preparedstatement.setString(5, headima);
            preparedstatement.setLong(6, l);
            preparedstatement.setString(7, word);

            int i = preparedstatement.executeUpdate();
            if (i != 1)
                return false;
            if (preparedstatement != null)
                preparedstatement.close();
            if (conn != null)
                conn.close();
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 获取系统的配置信息，包括标题，每页显示留言条数。
     *  
     */
    public void getconfig() {
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select `title`,`pageshownumber` from `guestbook_admin` where `id`=4");
            ResultSet resultset = preparedstatement.executeQuery();
            resultset.next();
            title = resultset.getString(1);
            pageshownumber = resultset.getInt(2);
            resultset.close();
            preparedstatement.close();
        } catch (Exception exception) {
            error = exception.toString();
        }
    }

    /**
     * 获取标题
     * 
     * @return
     */
    public String gettitle() {
        return title;
    }

    /**
     * 获取每页显示条数
     * 
     * @return
     */
    public int getpageshownumber() {
        return pageshownumber;
    }

    /**
     * 获取留言总数
     * 
     * @return
     */
    public int getmes_total() {
        return mes_total;
    }

    /**
     * 设置管理员用户
     * 
     * @param s
     */
    public void setadm_user(String s) {
        adm_user = s;
    }

    /**
     * 设置管理员密码
     * 
     * @param s
     */
    public void setadm_psw(String s) {
        adm_psw = s;
    }

    /**
     * 获取分页总数
     * 
     * @return
     */
    public int getpage_total() {
        return page_total;
    }

    /**
     * 获取当前页面
     * 
     * @param i
     */
    public void currentpage(int i) {
        currentpage = i;
    }

    /**
     * 获取留言总数
     *  
     */
    public void mes_total() {
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select count(*) as `total` from `guestbook`");
            ResultSet resultset = preparedstatement.executeQuery();
            resultset.next();
            mes_total = resultset.getInt(1);
            resultset.close();
            preparedstatement.close();
        } catch (Exception exception) {
            error = exception.toString();
            exception.printStackTrace();
        }
    }

    /**
     * 计算全部留言页面
     */
    public void page_total() {
        double d = (double) mes_total / (double) pageshownumber;
        double d1 = mes_total / pageshownumber;
        if (d > d1)
            page_total = (int) d1 + 1;
        else
            page_total = (int) d1;
    }

    /**
     * 获取留言总数
     * 
     * @return resultset结果集
     */
    public ResultSet query() {
        ResultSet resultset;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select * from `guestbook` order by `time` desc limit ?,?");
            int i = (currentpage - 1) * pageshownumber;
            preparedstatement.setInt(1, i);
            preparedstatement.setInt(2, pageshownumber);
            resultset = preparedstatement.executeQuery();
            return resultset;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return null;
        }
    }

    /**
     * 管理员认证
     * 
     * @return
     */
    public boolean admCheck() {
        int i = 0;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select `id` from `guestbook_admin` where `user`='"
                            + adm_user + "' and `psw`='" + adm_psw + "'");
            ResultSet resultset;
            for (resultset = preparedstatement.executeQuery(); resultset.next();)
                i++;

            resultset.close();
            preparedstatement.close();
            if (i != 1)
                return false;
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 管理员登陆
     * 
     * @param user
     * @param password
     * @return
     */
    public boolean admLogin(String user, String password) {
        int i = 0;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select `id` from `guestbook_admin` where `user`='"
                            + user + "' and `psw`=PASSWORD('" + password + "')");
            ResultSet resultset;
            for (resultset = preparedstatement.executeQuery(); resultset.next();)
                i++;

            resultset.close();
            preparedstatement.close();
            if (i != 1)
                return false;
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 获取用户的密码
     * 
     * @param user
     * @param password
     * @return
     */
    public String getPassword(String user, String password) {
        String s2 = null;

        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("select `id`,`psw` from `guestbook_admin` where `user`='"
                            + user + "' and `psw`=PASSWORD('" + password + "')");

            ResultSet resultset = preparedstatement.executeQuery();
            resultset.next();
            s2 = resultset.getString(2);
            resultset.close();
            return s2;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return null;
        }
    }

    /**
     * 删除留言
     * 
     * @param i
     * @return
     */
    public boolean delete(int i) {
        int j;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("delete from `guestbook` where `id`=?");
            preparedstatement.setInt(1, i);
            j = preparedstatement.executeUpdate();
            preparedstatement.close();
            if (j != 1)
                return false;
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 更新系统信息
     * 
     * @param title 留言簿标题
     * @param num	留言本每页显示留言条数
     * @return
     */
    public boolean system(String title, int num) {
        int j;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("update `guestbook_admin` set `title`=?,`pageshownumber`=?");
            preparedstatement.setString(1, title);
            preparedstatement.setInt(2, num);
            j = preparedstatement.executeUpdate();
            preparedstatement.close();
            if (j != 1)
                return false;
            return true;
        } catch (Exception exception) {
            exception.printStackTrace();
            error = exception.toString();
            return false;
        }
    }

    /**
     * 更改用户的密码
     * 
     * @param user
     * @param oldpass
     * @param newpass
     * @return
     */
    public boolean changepsw(String user, String oldpass, String newpass) {
        int i;
        try {
            PreparedStatement preparedstatement = conn
                    .prepareStatement("update `guestbook_admin` set `psw`=PASSWORD('"
                            + newpass
                            + "') where `user`='"
                            + user
                            + "' and `psw`=PASSWORD('" + oldpass + "')");
            i = preparedstatement.executeUpdate();
            preparedstatement.close();
            error = String.valueOf(i);
            if (i != 1)
                return false;
            return true;
        } catch (Exception ex) {
            ex.printStackTrace();
            error = ex.toString();
            return false;
        }
    }
}