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>