title: hibernate.connection.isolation being ignored?
body: <p>I am trying to set isolation level READ_UNCOMMITED as the default isolation level for all my application.</p>
  
  <p>My configuration:</p>
  
  <pre><code>@Configuration
  @EnableTransactionManagement
  @EnableJpaRepositories(entityManagerFactoryRef = "myappEntityManagerFactory", transactionManagerRef = "myappTransactionManager", basePackages = {
          "com.example.dao" })
  public class MyappDatabaseConfig {
  
      @Value("${myapp.datasource.db.driver}")
      private String DB_DRIVER;
  
      (...)
  
      @Bean(name = "myappDataSource")
      @Primary
      @ConfigurationProperties(prefix = "myapp.datasource")
      public DataSource myappDataSource() {
  
          DriverManagerDataSource dataSource = new DriverManagerDataSource();
  
          dataSource.setDriverClassName(DB_DRIVER);
          dataSource.setUrl(DB_URL);
          dataSource.setUsername(DB_USERNAME);
          dataSource.setPassword(DB_PASSWORD);
  
          return dataSource;
      }
  
      @Bean(name = "myappEntityManagerFactory")
      @Primary
      public LocalContainerEntityManagerFactoryBean myappEntityManagerFactory(EntityManagerFactoryBuilder builder,
              @Qualifier("myappDataSource") DataSource myappDataSource) {
  
          Properties props = new Properties();
          props.put("hibernate.dialect", HIBERNATE_DIALECT);
          props.put("hibernate.show_sql", HIBERNATE_SHOW_SQL);
          props.put("hibernate.hbm2ddl.auto", HIBERNATE_HBM2DDL_AUTO);
          props.put("hibernate.connection.isolation", Isolation.READ_UNCOMMITTED);
  
          LocalContainerEntityManagerFactoryBean factoryBean = builder.dataSource(myappDataSource)
                  .packages(ENTITYMANAGER_PACKAGES_TO_SCAN).persistenceUnit("myapp").build();
  
          factoryBean.setJpaProperties(props);
  
          return factoryBean;
      }
  
      @Bean(name = "myappTransactionManager")
      @Primary
      public PlatformTransactionManager myappTransactionManager(
              @Qualifier("myappEntityManagerFactory") EntityManagerFactory myappEntityManagerFactory) {
          return new JpaTransactionManager(myappEntityManagerFactory);
      }
  </code></pre>
  
  <p>But I still have to set isolation level individually</p>
  
  <p>Example:</p>
  
  <pre><code>@Controller
  public class MyappController {
  
      @RequestMapping(value = "/items", method = RequestMethod.GET)
      @ResponseBody
      @Transactional
      public List&lt;Items&gt; getItems() {
  
      }
  </code></pre>
  
  <p>Will not read uncommited unless I add isolation level again</p>
  
  <pre><code>@Controller
  public class MyappController {
  
      @RequestMapping(value = "/items", method = RequestMethod.GET)
      @ResponseBody
      @Transactional(value = "myappTransactionManager", isolation = Isolation.READ_UNCOMMITTED)
      public List&lt;Items&gt; getItems() {
  
      }
  </code></pre>
  
  <p>Am I missing something in my configuration? </p>
  
  <pre><code>    props.put("hibernate.connection.isolation", Isolation.READ_UNCOMMITTED);
  </code></pre>
  
  <p>Is not enough?</p>