SqlSessionFactory rebuild when "configLocation" and "configuration" are both null

[Flaming-Lin]

Version Info

mybatis-spring：2.0.3

Problem

I wanna register a "DefaultEnumTypeHandler" when creating bean "sqlSessionFactory". but if "configLocation" and "configuration" are both null, the "sqlSessionFacotry" will rebuild and my settings are invalid.

Bean register code：

    @Bean
    public SqlSessionFactoryBean sqlSessionFactory(@Qualifier("blogDataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
        factoryBean.setDataSource(dataSource);
        // if there is no "configLocation" or "configuration"
        // factoryBean.setConfiguration(new org.apache.ibatis.session.Configuration());

        SqlSessionFactory factory = factoryBean.getObject();
        if (null == factory) {
            throw new Exception("No sql session factory found!");
        }
        factory.getConfiguration().getTypeHandlerRegistry().setDefaultEnumTypeHandler(AutoEnumTypeHandler.class);
        return factoryBean;
    }

Source code：

Method "afterPropertiesSet" will be called when getting the bean instance. Then it will try to build a "sqlSessionFactory".

@Override
  public void afterPropertiesSet() throws Exception {
    notNull(dataSource, "Property 'dataSource' is required");
    notNull(sqlSessionFactoryBuilder, "Property 'sqlSessionFactoryBuilder' is required");
    state((configuration == null && configLocation == null) || !(configuration != null && configLocation != null),
        "Property 'configuration' and 'configLocation' can not specified with together");

    this.sqlSessionFactory = buildSqlSessionFactory();
  }

Here is the root cause, "targetConfiguration" will be a new instance of "Configuration" when "configLocation" and "configuration" are both null. Then the "DefaultEnumTypeHandler" will initialize and my settings turn invalid.

protected SqlSessionFactory buildSqlSessionFactory() throws Exception {

    final Configuration targetConfiguration;

    XMLConfigBuilder xmlConfigBuilder = null;
    if (this.configuration != null) {
      targetConfiguration = this.configuration;
      if (targetConfiguration.getVariables() == null) {
        targetConfiguration.setVariables(this.configurationProperties);
      } else if (this.configurationProperties != null) {
        targetConfiguration.getVariables().putAll(this.configurationProperties);
      }
    } else if (this.configLocation != null) {
      xmlConfigBuilder = new XMLConfigBuilder(this.configLocation.getInputStream(), null, this.configurationProperties);
      targetConfiguration = xmlConfigBuilder.getConfiguration();
    } else {
      LOGGER.debug(
          () -> "Property 'configuration' or 'configLocation' not specified, using default MyBatis Configuration");
      // 【Here】
      targetConfiguration = new Configuration();
      Optional.ofNullable(this.configurationProperties).ifPresent(targetConfiguration::setVariables);
    }

[kazuki43zoo]

If call the SqlSessionFactoryBean#getObject in @Bean method, please return a SqlSessionFactory instance instead of return a SqlSessionFactoryBean instance.

@Bean
public SqlSessionFactory sqlSessionFactory(@Qualifier("blogDataSource") DataSource dataSource) throws Exception {
  SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
  factoryBean.setDataSource(dataSource);
  // if there is no "configLocation" or "configuration"
  // factoryBean.setConfiguration(new org.apache.ibatis.session.Configuration());
  factoryBean.afterPropertiesSet();
  SqlSessionFactory factory = factoryBean.getObject();
  factory.getConfiguration().getTypeHandlerRegistry().setDefaultEnumTypeHandler(AutoEnumTypeHandler.class);
  return factory;
}

[kazuki43zoo]

I will add new property for customizing the defaultEnumTypeHandler on gh-458.

[kazuki43zoo]

Improved via gh-458.