com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: канал связи [дубликат]

На этот вопрос уже есть ответ здесь:

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: сбой линии связи 32 ответа

Я использую Mac OS X Lion версии 10.8. У меня установлен MySQL через XAMPP. И я добавил mysql и драйвер jdbc (5.1.22) в мой путь к классам. Следующий простой код не работает:

package learning.database;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class Simple {

Connection getConnection() throws SQLException{
String url = "jdbc:mysql://localhost/";
return DriverManager.getConnection(url, "username", "password");
}

void createDatabase(String database, Connection conn) throws SQLException{
Statement stmt = null;
try {
stmt = conn.createStatement();
stmt.executeUpdate("drop database if exists "+database);
stmt.executeUpdate("create database "+database);
}finally {
if(null != stmt)
stmt.close();
}
}

public static void main(String args[]) throws Exception{
String school = "school";
Classroom cr = new Classroom();
Connection conn = cr.getConnection();
cr.createDatabase(school, conn);
}
}

Когда я запускаю код, я получаю следующую ошибку:

Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:350)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2408)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2445)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2230)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:813)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:334)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at learning.database.Classroom.getConnection(Classroom.java:43)
at learning.database.Simple.main(Simple.java:33)
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:432)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at java.net.Socket.(Socket.java:375)
at java.net.Socket.(Socket.java:218)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:300)
... 16 more

Кто-нибудь знает, как решить эту проблему?