@EnableTransactionManagement
public class JPAConfiguration {

    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean factoryBean = new LocalContainerEntityManagerFactoryBean();

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        factoryBean.setJpaVendorAdapter(vendorAdapter);

        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setUsername("root");
        dataSource.setPassword("");
        dataSource.setUrl("jdbc:mysql://localhost:3306/casadocodigo");
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");

        factoryBean.setDataSource(dataSource);

        Properties props = new Properties();
        props.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");
        props.setProperty("hibernate.show_sql", "true");
        props.setProperty("hibernate.hbm2ddl.auto", "update");
        factoryBean.setJpaProperties(props);

        factoryBean.setPackagesToScan("br.com.casadocodigo.loja.models");

        return factoryBean;
    }

    @Bean
    public JpaTransactionManager transactionManager(EntityManagerFactory emf) {
        return new JpaTransactionManager(emf);
    }
}

Segui todos os passos exatamente da mesma forma. Porém estou tendo um erro ao realizar a conexão com o banco. Estou usando a versão 5.7.23 do Mysql no Ubuntu.

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open JPA EntityManager for transaction; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.JDBCConnectionException: Could not open connection org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:973)

Root Cause

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Client does not support authentication protocol requested by server; consider upgrading MySQL client