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Java Mysql: ClassNotFoundException -> Could not find driver [duplicate]

This question already has answers here: Closed 11 years ago.

Possible Duplicate:

ClassNotFoundException com.mysql.jdbc.Driver

I have included the mysql-connector-java-5.1.16-bin.jar into my Eclipse library, this code is based on tutorials that I have found on the web since I haven't used MySQL in Java before. Unfortunately I dont see where I use the acutual mysql-connector-java-5.1.16-bin.jar and the console prints Could not find driver. meaning the ClassNotFoundException is thrown. Do you see the (probably obvious) problem here that I dont see?

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.sql.Timestamp;

public class MysqlConnector {

    private static MysqlConnector instance = null;
    private static Connection conn = null;

    private static String dbHost = "localhost";
    private static String dbPort = "3306";
    private static String database = "sample";
    private static String dbUser = "root";
    private static String dbPassword = "";

    public MysqlConnector() {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection("jdbc:mysql://" + dbHost + ":"
                    + dbPort + "/" + database + "?" + "user=" + dbUser + "&"
                    + "password=" + dbPassword);
        } catch (ClassNotFoundException e) {
            System.out.println("Could not find driver."); //TODO LOGGER
        } catch (SQLException e) {
            System.out.println("Could not connect to database."); //TODO LOGGER
        }
    }

    public static MysqlConnector getInstance()
    {
        if(instance == null)
            instance = new MysqlConnector();
        return instance;
    }

    public boolean validateApiKey(String apikey)
    {
        if(conn != null)
        {
            Statement query;
            try {
                query = conn.createStatement();

                String sql = "SELECT startdate, expiration, active " + "FROM apikeys "
                        + "WHERE apikey = '" + apikey +"'";
                ResultSet result = query.executeQuery(sql);

                if(result.getFetchSize()>0 && result.getInt("active")==1){
                    Date now = new Date();
                    Date startdate = result.getDate("startdate");
                    Date expirationdate = result.getDate("expiration");
                    if(now.before(expirationdate) && now.after(startdate)){
                        return true;
                    } else {
                        return false;
                    }
                } else {
                    return true;
                }
            } catch (SQLException e) {
                e.printStackTrace();
                return false;
         开发者_StackOverflow社区   }
        }
        return false;
    }

}


Right click your project > Build Path > Add libraries and add the jar file.

Also make sure that it is on your runtime path. Right click the main class > run as > run configurations > Classpath


The only thing I see is that you need to add the library of the MySQL Connector in your project not only in your Eclipse Library.


how do you run this?

you instantiate a class from that jar when you do

Class.forName("com.mysql.jdbc.Driver")

http://download.oracle.com/javase/1.4.2/docs/api/java/lang/Class.html#forName%28java.lang.String%29

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