JavaWeb实现简单查询商品功能

package com.subing.web;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;@WebServlet("/CustomerServlet")public class CustomerServlet extends HttpServlet {  private static final long serialVersionUID = 1L;  private SqlDemo sql = null;  private final static String s1 = "<h1>欢迎进入管理页面</h1><form action='CustomerServlet' method='post'> "      + "精确查询:<input type='text' name='jqmess'/><br>"      + "模糊查询:<input type='text' name='mhmess'/><br>"      + "<input type='submit' value='提交' name='sub'/>"      + "</form>";  // 登录的时候进行验证  private boolean isLoginProv(String userinfo, String password) {    if (userinfo != null && userinfo.length() > 0 && password != null        && password.length() > 0) {      return true;    }    return false;  }  public CustomerServlet() throws Exception {    super();    sql = new SqlDemo(); // 进行数据库访问的类    // TODO Auto-generated constructor stub  }  /**   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse   *   response)   */  protected void doGet(HttpServletRequest request,      HttpServletResponse response) throws ServletException, IOException {    // TODO Auto-generated method stub    this.doPost(request, response);  }  /**   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse   *   response)   */  protected void doPost(HttpServletRequest request,      HttpServletResponse response) throws ServletException, IOException {    response.setContentType("text/html;charset=gb2312");    request.setCharacterEncoding("gb2312");    PrintWriter pw = response.getWriter();    String sub = request.getParameter("sub");    String login = request.getParameter("login");    if (login != null && login.length() > 0) {      String admin_id = request.getParameter("admin_id");      String password = request.getParameter("password");      if (isLoginProv(admin_id, password)) {        try {          if (sql.loginVerify(admin_id, password)) {            pw.println(s1);          } else {            pw.println("<h1>登录失败！</h2>2秒自动跳转到登录页面!");            response.setHeader("refresh", "2;url=login.html");          }        } catch (Exception e) {          e.printStackTrace();        }      } else {        pw.println("<h1>登录失败！</h2>5秒自动跳转到登录页面!");        response.setHeader("refresh", "5;url=login.html");      }    } else if (sub != null && sub.length() > 0) {      pw.println(s1);      String jqmess = request.getParameter("jqmess");      String mhmess = request.getParameter("mhmess");      if (jqmess != null && jqmess.length() > 0) {        try {          String s = sql.getJqMess(jqmess);          String mess[] = s.split(",");          String html = "<table border='5'>" + "<tr>" + "<th>Id号码</th>"              + "<th>商品名称</th>" + "<th>商品价格</th>"              + "<th>商品库存数量</th>" + "<th>商品描述</th>";          String main = "<tr>" + "<td>" + mess[0] + "</td>" + "<td>"              + mess[1] + "</td>" + "<td>" + mess[2] + "</td>"              + "<td>" + mess[3] + "</td>" + "<td>" + mess[4]              + "</td></tr></table>";          String head = html + main;          pw.println(head);        } catch (Exception e) {          e.printStackTrace();        }      } else if (mhmess != null && mhmess.length() > 0) {        try {          String head = "";          String html = "<table border='5'>" + "<tr>" + "<th>Id号码</th>"              + "<th>商品名称</th>" + "<th>商品价格</th>"              + "<th>商品库存数量</th>" + "<th>商品描述</th>";          head += html;          String s = sql.getMhMess(mhmess);          String m[] = s.split(",,");          for (int i = 0; i < m.length; i++) {            String mess[] = m[i].split(",");            String main = "<tr>" + "<td>" + mess[0] + "</td>"                + "<td>" + mess[1] + "</td>" + "<td>" + mess[2]                + "</td>" + "<td>" + mess[3] + "</td>" + "<td>"                + mess[4] + "</td></tr>";            head += main;          }          head += "</table>";          pw.println(head);        } catch (Exception e) {          e.printStackTrace();        }      }    }  }}

package com.subing.web;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;public class SqlDemo {  private Connection conn = null;  private PreparedStatement preparedStatement = null;  public SqlDemo() throws Exception {    conn = getConnection();  }  private Connection getConnection() throws Exception {    String driverClass = "com.mysql.jdbc.Driver";    String url = "jdbc:mysql:///shop?useUnicode=true&characterEncoding=gb2312";    String user = "root";    String password = "12345";    // 注册加载驱动    Class.forName(driverClass);    // 获取连接    Connection conn = DriverManager.getConnection(url, user, password);    System.out.println(conn);    return conn;  }  // 登录的时候 进行验证  public boolean loginVerify(String userinfo, String password)      throws Exception {    String sql = "select * from admin where admin_id = ?";    preparedStatement = conn.prepareStatement(sql);    preparedStatement.setString(1, userinfo);    ResultSet rs = preparedStatement.executeQuery();    if (rs.next()) {      if (rs.getString("password").equals(password)) {        System.out.println("成功！");        return true;      }    }    System.out.println("失败！");    return false;  }  public String getJqMess(String admin_id) throws Exception {    String s = "";    String sql = "select * from product1 where product_id = ? OR product_name LIKE ?"        + "OR product_price LIKE ?"        + "OR product_num LIKE ?"        + "OR product_describe LIKE ?";    preparedStatement = conn.prepareStatement(sql);    preparedStatement.setString(1, admin_id);    preparedStatement.setString(2, admin_id);    preparedStatement.setString(3, admin_id);    preparedStatement.setString(4, admin_id);    preparedStatement.setString(5, admin_id);    //查询到记录的时候，返回一个resultSet，也处理了该方法查找失败的时候返回null的情况    ResultSet rs = preparedStatement.executeQuery();    while (rs.next()) {      s = rs.getInt(1) + "," + rs.getString(2) + "," + rs.getInt(3) + ","          + rs.getInt(4) + "," + rs.getString(5);    }    return s;  }  public String getMhMess(String admin_id) throws Exception {    String mess = "";    String sql = "select * from product1 where product_id like ? OR product_name LIKE ? OR product_price LIKE ? OR product_num LIKE ?"        + "OR product_describe LIKE ?";    preparedStatement = conn.prepareStatement(sql);    preparedStatement.setString(1, "%" + admin_id + "%");    preparedStatement.setString(2, "%" + admin_id + "%");    preparedStatement.setString(3, "%" + admin_id + "%");    preparedStatement.setString(4, "%" + admin_id + "%");    preparedStatement.setString(5, "%" + admin_id + "%");    ResultSet rs = preparedStatement.executeQuery();    while (rs.next()) {      String s = rs.getInt(1) + "," + rs.getString(2) + ","          + rs.getInt(3) + "," + rs.getInt(4) + "," + rs.getString(5);      mess += s + ",,";    }    return mess;  }  public static void main(String[] args) throws Exception {    SqlDemo sqlDemo = new SqlDemo();    String s = sqlDemo.getMhMess("xi");    String m[] = s.split(",,");    for (int i = 0; i < m.length; i++) {      System.out.println(m[i]);    }  }}

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body>  <h1>登录</h1>  <form action="CustomerServlet" method="post">    账号:<input type="text" name="admin_id"/>    密码:<input type="password" name="password"/>    <input type="submit" value="登录" name="login"/>  </form>        </body></html>