在 java 和 mysql 之间建立连接时出错

Question

Following are my code.......

import java.sql.*;
public class ConnectionTry {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try
        {
            System.out.println(1);
            Class.forName("com.mysql.jdbc.Driver");
            System.out.println(2);
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/Test","root","password");
            if(!conn.isClosed())
            {
                System.out.println("connected");
            }
            System.out.println(3);
            PreparedStatement ps = conn.prepareStatement("insert into User(user_id,user_name,email,password) values (?,?,?,?);");
            System.out.println(4);      
            ps.setInt(1, 45);
            System.out.println(5);
            ps.setString(2, "@Suraj");
            ps.setString(3, "esuraj@gmail.com");
            ps.setString(4, "qwer1234");
            int x = ps.executeUpdate();
            if(x > 0) {
                System.out.println("Registration Successful");
            }
            else {
                System.out.println("Registration not Successful");
            }
        }
        catch(Exception c) {
            System.out.println(c.getMessage());
        }

    }

}

In the above code: Test is database, root is user in mysql, password is mysql password.

Following error occur when I run the above code.

Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.

Answer 1

Try and set the character encoding like the error is telling you to do.

jdbc:mysql://localhost/Test?characterEncoding=utf8

Answer 2

you didnt specify the port on the URL database connection which is by default 3306 and you url should look like this jdbc:mysql://localhost:3306/Test

Answer 3

this core jdbc file

import java.sql.*;

public class jdbcInsertTable {

    public static void insertvalue() throws SQLException{

        try {
            Class.forName("com.mysql.jdbc.Driver");
            System.out.println("Connecting to a selected database...");

            Connection con= DriverManager.getConnection
                    ("jdbc:mysql://localhost:3306/oracl","root","root");
            System.out.println("Connected database successfully...");

            Statement stmt = con.createStatement();
            stmt.executeUpdate("insert into employee values('sagar','sales')");
            System.out.println("values insert successfully");

            con.close();

        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            System.out.println(e);
        }

    }
    public static void main(String[] args) throws SQLException {
        // TODO Auto-generated method stub

        insertvalue();
    }

}