Erro de org.hibernate.exception.JDBCConnectionException no Hibernate

Pessoal estou tendo problemas na conexão, abaixo vou colocar os códigos.

<?xml version="1.0" encoding="UTF-8"?>
<session-factory>

    <!-- Configurações da conexão com banco -->
    <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="connection.url">jdbc:mysql://localhost:3306/vendas</property>
    <property name="connection.username">root</property>
    <property name="connection.password">25251606</property>

    <!-- Configuração da conexão JDBC Mysql -->
    <property name="connection.pool_size">1</property>

    <!-- SQL dialect -->
    <property name="dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>

    <!-- Gerenciamento da sessão mysql -->
    <property name="current_session_context_class">thread</property>

    <!-- Desabilita o cache  -->
    <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>

    <!-- Exibe os comandos mysql -->
    <property name="show_sql">true</property>

    <!-- Criação e atualização das tabelas -->
    <property name="hbm2ddl.auto">update</property>

package br.com.Vendas.util;

import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

public class HibernateUtil {

private static final SessionFactory sessionFactory = buildSessionFactory();

private static SessionFactory buildSessionFactory() {
    try {
    	
    	Configuration configuration = new Configuration();
    	configuration.configure();
    	
    	ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
    			.applySettings(configuration.getProperties()).build();
    	
    	SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry);
    	
    	return sessionFactory;
    	
         //Cria uma conexão a partir do hibernate.cfg.xml
       // return new Configuration().configure().buildSessionFactory(
		   // new StandardServiceRegistryBuilder().build() );
    }
    catch (Throwable ex) {
        // Mensagem de erro ao conectar
        System.out.println("Criação inicial do objeto SeesionFactory falhou. Erro: " + ex);
        throw new ExceptionInInitializerError(ex);
    }
}

public static SessionFactory getSessionFactory() {
    return sessionFactory;
}

}

Os erros são

Caused by: org.hibernate.exception.JDBCConnectionException: Error calling Driver#connect

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

Caused by: java.lang.NullPointerException