本文实例为大家分享了JavaWeb实现简单查询商品功能的具体代码,供大家参考,具体内容如下
CustomerServlet.java
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(); } } } } }
数据库访问类:
SqlDemo.java
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]); } } }
html文件:
login.html
<!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>
数据库里面的表数据
运行效果
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持呐喊教程。
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