使用Java/JavaWeb实现数据库的增删改查操作
最编程
2024-01-02 09:36:46
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package com.bjpowernode.javaweb.servlet;
import com.bjpowernode.javaweb.utils.DButil;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
@WebServlet(name = "edit",value = "/edit")
public class Edit extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String contextPath = request.getContextPath();
response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("UTF-8");
PrintWriter out =response.getWriter();
//jsp文档
out.println("<html lang='en'>");
out.println("<head>");
out.println(" <meta charset='UTF-8'>");
out.println(" <link href='h/favicon2.ico' rel='icon' type='image/x-icon'/>");
out.println(" <title>添加信息</title>");
out.println(" <style>");
out.println(" body {");
out.println(" background-color:#FDF5E6;");
out.println(" }");
out.println(" </style>");
out.println(" <style>");
out.println(" body {");
out.println(" width: 100%;");
out.println(" height: 100%;");
out.println(" background: url('./img/olypic.jpg');");
out.println(" background-repeat: no-repeat;");
out.println(" background-size: 100% 100%;");
out.println(" background-attachment: fixed;");
out.println(" }");
out.println(" </style>");
out.println(" <style>");
out.println(" input{");
out.println(" width: 20%;");
out.println(" padding: 12px 20px;");
out.println(" margin: 8px 0;");
out.println(" box-sizing: border-box;");
out.println(" border: 1px solid #555;");
out.println(" outline: none;");
out.println(" }");
out.println("");
out.println(" input:focus {");
out.println(" background-color: lightblue;");
out.println(" }");
out.println(" </style>");
out.println(" <style>");
out.println(" #boxshadow {");
out.println(" position: relative;");
out.println(" -moz-box-shadow: 1px 2px 4px rgba(0, 0, 0,0.5);");
out.println(" -webkit-box-shadow: 1px 2px 4px rgba(0, 0, 0, .5);");
out.println(" box-shadow: 1px 2px 4px rgba(0, 0, 0, .5);");
out.println(" padding: 10px;");
out.println(" background:#F0F8FF;");
out.println(" border-radius:8px;");
out.println(" }");
out.println("");
out.println(" /* Make the image fit the box */");
out.println(" #boxshadow img {");
out.println(" width: 50%;");
out.println(" border: 0px solid #8a4419;");
out.println(" border-style: inset;");
out.println(" }");
out.println("");
out.println(" #boxshadow::after {");
out.println(" content: '';");
out.println(" position: absolute;");
out.println(" z-index: -1; /* hide shadow behind image */");
out.println(" -webkit-box-shadow: 0 15px 20px rgba(0, 0, 0, 0.3);");
out.println(" -moz-box-shadow: 0 15px 20px rgba(0, 0, 0, 0.3);");
out.println(" box-shadow: 0 15px 20px rgba(0, 0, 0, 0.3);");
out.println(" width: 70%;");
out.println(" left: 15%; /* one half of the remaining 30% */");
out.println(" height: 100px;");
out.println(" bottom: 0;");
out.println(" }");
out.println(" </style>");
out.println(" <style>");
out.println(" .button {");
out.println(" background-color:#337AB7; /* Green */");
out.println(" border: none;");
out.println(" color: white;");
out.println(" padding: 16px 32px;");
out.println(" text-align: center;");
out.println(" text-decoration: none;");
out.println(" display: inline-block;");
out.println(" font-size: 16px;");
out.println(" margin: 4px 2px;");
out.println(" -webkit-transition-duration: 0.4s; /* Safari */");
out.println(" transition-duration: 0.4s;");
out.println(" cursor: pointer;");
out.println(" }");
out.println("");
out.println(" .button1 {");
out.println(" background-color: white;");
out.println(" color: black;");
out.println(" border: 2px solid #337AB7;");
out.println(" }");
out.println(" .button1:hover {");
out.println(" background-color: #337AB7;");
out.println(" color: white;");
out.println(" box-shadow: 0 12px 16px 0 rgba(0,0,0,0.24),0 17px 50px 0 rgba(0,0,0,0.19);");
out.println(" }");
out.println(" </style>");
out.println("");
out.println("</head>");
out.println("<body>");
out.println("");
out.println("<div style='padding:2px;width:1080px;height:470px;margin-top:10%;margin-left:20%;opacity: 0.8' id='boxshadow'>");
out.println(" <div>");
out.println(" <img src='img/olypic.jpg' style='float:left;margin-top:5%;'>");
out.println(" </div>");
out.println(" <div style='float:right;'>");
out.println(" <form action='"+contextPath+"/update' method='post'>");
//获取国家名称
String country=request.getParameter("name");
//连接数据库
Connection conn=null;
PreparedStatement ps=null;
ResultSet rs=null;
try {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
//获取连接
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mofa", "root", "123456");
String sql = "select * from medals_table where Country=?";
//编译sql语句
ps = conn.prepareStatement(sql);
//赋值 第一个问好赋值 country 国家名称
ps.setString(1, country);
//查询返回结果集 这个结果集只有一条记录 ，国家名称是主键 ， 故只有一条数据
rs = ps.executeQuery();
if(rs.next()){
String logo=rs.getString("logo");
String Glod = rs.getString("Glod_num");
String Silver = rs.getString("Silver_num");
String Copper = rs.getString("Copper_num");
String sum=rs.getString("Sum");
String id=rs.getString("id");
System.out.println("你好，你好，你好，齐天大圣！！！");
//输出动态网页
out.println("<p style='margin-right:200px;'>");
out.println(" 国家名称   <input type='text' name='Country' value='"+country+"' style='border-radius:8px;width:150px;height:30px;'>");
out.println(" </p>");
// out.println(" <p>");
// out.println("    logo      <input type='text' name='logo' value='"+logo+"' style='border-radius:8px;width:150px;height:30px;margin-top:1%'>");
// out.println(" </p>");
out.println(" <p>");
out.println("   金牌数     <input type='text' name='Glod_num' value='"+Glod+"' style='border-radius:8px;width:150px;height:30px;margin-top:1%'>");
out.println(" </p>");
out.println("");
out.println(" <p>");
out.println("   银牌数     <input type='text' name='Silver_num' value='"+Silver+"' style='border-radius:8px;width:150px;height:30px;margin-top:1%'>");
out.println(" </p>");
out.println(" <p>");
out.println("   铜牌数     <input type='text' name='Copper_num' value='"+Copper+"' style='border-radius:8px;width:150px;height:30px;margin-top:1%'>");
out.println(" </p>");
out.println(" <p>");
out.println("      id           <input type='text' name='id' value='"+id+"' style='border-radius:8px;width:150px;height:30px;margin-top:1%'>");
out.println(" </p>");
}
} catch (SQLException e) {
e.printStackTrace();
}finally {
DButil.close(conn,ps,rs);
}
out.println(" <input type='submit' value='保存'/><br/>");
out.println(" </form>");
out.println(" </form>");
out.println(" </div>");
out.println("</div>");
out.println("</body>");
out.println("</html>");
}
}
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使用Java/JavaWeb实现数据库的增删改查操作