connecting to mysql in java
Question
I am very beginner in java programming. I use eclipse IDE to write my code.I create a project and want to connect to mysql. At first,i install apache 9 and then open eclipse and create my project and then install mysql 8. When I run my code,"java.lang.ClassNotFoundException: com.mysql.jdbc.Driver" is shown. I have taken image from my project.
https://www.imgurl.ir/uploads/r22886_.jpg
Please help me. Thank you.
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" buffer="none"%>
<%@ page import="java.io.*,java.util.*,java.sql.*" %>
<%@ page import = "javax.servlet.http.*,javax.servlet.*" %>
<html>
<head>
<title>First java web</title>
</head>
<body>
<%
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(ClassNotFoundException ex)
{
out.print(ex.toString());
}
catch(Exception e)
{
out.print(e.toString());
}
%>
</body>
</html>
2 answers
solution1
1 2019-02-06 06:18:08
Please put your jdbc connection in Servlet or better yet create a database layer in your code that handles db connection and data manipulations after you get your data. Now to answer your question
import java.sql.*;
class MysqlCon{
public static void main(String args[]){
try{
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb","root","root");
//here mydb is database name, root is username and password
Statement stmt=con.createStatement();
ResultSet rs=stmt.executeQuery("select * from emp");
while(rs.next())
System.out.println(rs.getInt(1)+" "+rs.getString(2)+" "+rs.getString(3));
con.close();
} catch(Exception e) {
System.out.println(e);
}
}
}
solution2
0 2019-02-06 06:42:57
It looks like you are not familiar with Servlets and Patterns like MVC. I recommend you to have a look at some tutorials because extensibility is a very important point in software development. The way you are starting in your example will result in spagehetti code it won't be fun to continue developing. As a Tip: If you want to develop in java you can also have a look at the Spring tool suite (Sts) Framework. I makes java development very easy and you got some great tutorial to have a quick start. Python with Flask is also a good way to start with web development.
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