用java做网站，java连接数据库并查询输出到页面

news/2024/5/11 1:00:31/文章来源:https://blog.csdn.net/weixin_34095889/article/details/89698184

java web的后缀名是jsp，所以咱们要有一个jsp的开发环境，我这用的是jspStudy

自行百度。这软件是一个集成开发环境，安装启动后即可使用，集成了tomcat和mysql数据库

首先我们先新建一个首页文件

index.jsp

[java] view plaincopy 
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="UTF-8"%>  
<%@ page import="java.sql.Connection" %>  
<%@ page import="java.sql.DriverManager" %>  
<%@ page import="java.sql.SQLException" %>  
<%@ page import="java.sql.Statement" %>  
<%@ page import="java.sql.PreparedStatement" %>  
<%@ page import="java.sql.ResultSet" %>  
<!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>mysql测试</title>  
  
</head>  
<body>  
  
    <%  
             //此进行连接数据库  
            String url="jdbc:mysql://127.0.0.1:3306/test"; //test为数据库名称  
            String dbuser="root"; //数据库账户  
            String dbpwd="root"; //数据库密码  
            try   
            {  
                Class.forName("com.mysql.jdbc.Driver"); //加载驱动 JspStudy  
            }   
            catch (ClassNotFoundException e)   
            {   
                e.printStackTrace();  
            }    
            //取得数据库连接conn  
            Connection conn=DriverManager.getConnection(url, dbuser, dbpwd);;  
  
            PreparedStatement ps=null;  
            ResultSet rs=null;  
            //声明数据库字段  
            String id="";  
            String title="";  
            String img="";  
            try   
            {   
                String sql="select * from res";  
                ps = conn.prepareStatement(sql);  
                rs = ps.executeQuery();  
                while(rs.next())  
                {  
                    id=rs.getString(1);  
                    title=rs.getString(2);  
                    img=rs.getString(3);  
                    out.println("ID:"+id+"<br>");  
                    out.println(title+"<br><br>");   
                    out.println("<img src=\""+img+"\"/>"+"<br><br>");   
                }  
            }  
            catch (SQLException e)   
            {  
                e.printStackTrace();  
            }  
            finally  
            {   
                    try   
                    {  
                        if(rs!=null)              
                            rs.close();  
                    }   
                    catch (SQLException e)   
                    {  
                        e.printStackTrace();  
                    }  
                    finally  
                    {  
                            try   
                            {  
                                if(ps!=null)                      
                                    ps.close();  
                            }   
                            catch (SQLException e)   
                            {   
                                e.printStackTrace();  
                            }  
                            finally  
                            {  
                                try   
                                {  
                                    if(conn!=null)                    
                                        conn.close();  
                                }   
                                catch (SQLException e)   
                                {   
                                        e.printStackTrace();  
                                }  
                            }  
                    }  
            }   
    %>         
</body>  
</html>  