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Java

Posted by Anders Björkland
Anders Björkland
7,481 Points

What is the purpose of @Bean on method called by another @Bean method?

Hi,

In the class DataConfig from the video Making Service Calls from a Controller there are two methods; sessionFactory and dataSource. Is the dataSource method being used by Spring or is it only the sessionFactory method that uses it? If so, is the @Bean annotation needed? How come?

Here's the class: 

@Configuration
@PropertySource("app.properties")
public class DataConfig {
    @Autowired
    private Environment env;

    @Bean
    public LocalSessionFactoryBean sessionFactory() {
        Resource config = new ClassPathResource("hibernate.cfg.xml");
        LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
        sessionFactory.setConfigLocation(config);
        sessionFactory.setPackagesToScan(env.getProperty("giflib.entity.package"));
        sessionFactory.setDataSource(dataSource());
        return sessionFactory;
    }

    @Bean
    public DataSource dataSource() {
        BasicDataSource ds = new BasicDataSource();

        // Driver class name
        ds.setDriverClassName(env.getProperty("giflib.db.driver"));

        // Set URL
        ds.setUrl(env.getProperty("giflib.db.url"));

        // Set username & password
        ds.setUsername(env.getProperty("giflib.db.username"));
        ds.setPassword(env.getProperty("giflib.db.password"));

        return ds;
    }
}