标签：class doctype 内容类型 static version lex val sql数据库 span
web.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">
<servlet>
<servlet-name>FootballTeam</servlet-name>
<servlet-class>FindFootOrPk</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>FootballTeam</servlet-name>
<url-pattern>/foot</url-pattern>
</servlet-mapping>
</web-app>
html文件
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html调用servlet</title>
</head>
<body>
<h1 align="center">请点击提交按钮</h1>
<div align="center" class="footgame">
<form action="http://localhost:8080/ltb6w/foot" name="match" method="post">
<input type="submit" value="提交">
</form>
</div>
</body>
</html>
import java.sql.*;
import java.io.*;
import java.io.IOException;
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("/FindFootOrPk")
public class FindFootOrPk extends HttpServlet {
private static final long serialVersionUID = 1L;
//JDBC驱动名和数据库URL
static final String JDBC_DRIVER="com.mysql.jdbc.Driver";
static final String DB_URL="jdbc:mysql://localhost:3306/dudu";//dudu数据库名称
//数据库用户名和密码
static final String USER="root";
static final String PASS="123456";
/**
* @see HttpServlet#HttpServlet()
*/
public FindFootOrPk() {
super();
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
Connection conn=null;
Statement stmt=null;
//设置响应内容类型
response.setContentType("text/html;charset=UTF-8");
PrintWriter out=response.getWriter();
String title="前后端打通,连接数据库,我的世界来啦!";
// String name=request.getParameter("pk");
// String link=request.getParameter("link");
String docType = "<!DOCTYPE html>\n";
out.println(docType +
"<html>\n" +
"<head><title>" + title + "</title></head>\n" +
"<body bgcolor=\"#f0f0f0\">\n" +
"<h1 align=\"center\">" + title + "</h1>\n");
try{
// 注册 JDBC 驱动器
Class.forName("com.mysql.jdbc.Driver");
// 打开一个连接
conn = DriverManager.getConnection(DB_URL,USER,PASS);
out.println("数据库连接成功！");
// 执行 SQL 查询
stmt = conn.createStatement();//
String sql; //foot_ball 数据库表名称
sql = "SELECT*FROM foot_ball"; //sql语句,一定要保证正确.最好测试一下,要不html不显示.
ResultSet rs = stmt.executeQuery(sql); //sql语句执行的结果
// 展开结果集数据库
while(rs.next()){
// 通过字段检索
int id = rs.getInt("id");
String tream = rs.getString("tream");
String url = rs.getString("url");
// 输出数据
out.println("ID: " + id);
out.println(", 球队: " + tream);
out.println(", 站点 URL: " + url);
out.println("<br />");
}
out.println("</body></html>");
// 完成后关闭
rs.close();
stmt.close();
conn.close();
} catch(SQLException se) {
// 处理 JDBC 错误
se.printStackTrace();
} catch(Exception e) {
// 处理 Class.forName 错误
e.printStackTrace();
}finally{
// 最后是用于关闭资源的块
try{
if(stmt!=null)
stmt.close();
}catch(SQLException se2){
}
try{
if(conn!=null)
conn.close();
}catch(SQLException se){
se.printStackTrace();
}
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
标签：class doctype 内容类型 static version lex val sql数据库 span
原文地址：https://www.cnblogs.com/ltb6w/p/9906170.html
