ConfigurableApplicationContext c = new ConfigurableApplicationContext();
BeanDefinition bd = new BeanDefinition();
bd.setId("id");
bd.setClassName("classname");
bd.setProperty("propertyName", propertyValue");
...etc...

c.addBean("beanId", beanObject);

c.setAnnotationAware(true);
c.setAnnotationScanBasePackage("packagename");

c.addAnnotatedSpringClass("classnamethatisannotated");

@Configuration
public class AppConfig {
    @Bean
    public TransferService transferService() {
        return new TransferServiceImpl();
    }
}

def bb = new grails.spring.BeanBuilder()

bb.beans {
  dataSource(BasicDataSource) {
    driverClassName = "org.hsqldb.jdbcDriver"
    url = "jdbc:hsqldb:mem:grailsDB"
    username = "sa"
    password = ""
  }

  sessionFactory(ConfigurableLocalSessionFactoryBean) {
    dataSource = dataSource
    hibernateProperties = [ "hibernate.hbm2ddl.auto":"create-drop", "hibernate.show_sql":true ]
  }
}

@RunWith(AtUnit.class)
@Container(Container.Option.SPRING)
@MockFramework(MockFramework.Option.EASYMOCK)
public class ExampleSpringEasyMockTest {

    @Bean @Unit UserManagerImpl manager;
    @Bean("fred") User fred;
    @Bean("userDao") @Mock UserDao dao;
    @Bean("log") @Stub Logger log;

    @Test
    public void testGetUser() {
        expect(dao.load(1)).andReturn(fred);
        replay(dao);
        assertSame(fred, manager.getUser(1));
        verify(dao);
    }


}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">

  <bean id="userManager" class="atunit.example.subjects.UserManagerImpl">
      <constructor-arg ref="log"/>
      <property name="userDao" ref="userDao"/>
  </bean>

  <bean id="fred" class="atunit.example.subjects.User">
      <property name="id" value="500"/>
      <property name="username" value="fred"/>
  </bean>

</beans>

<import resource="classpath:production-context.xml">

<bean id="overriddenBean" class="com.MyClass">
   ....
</bean>

public class ABeanFactoryPostProcessor implements
        BeanFactoryPostProcessor {

    public void postProcessBeanFactory(
            ConfigurableListableBeanFactory beanFactory) throws BeansException {

    	    if (beanFactory instanceof BeanDefinitionRegistry) {
    		BeanDefinition beanDefinition=...

    	        ((BeanDefinitionRegistry)beanFactory).registerBeanDefinition(name, beanDefinition);
    	    }
    }

}

import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class Application implements CommandLineRunner {

    private static final Logger LOG = LoggerFactory.getLogger(Application.class);

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        LOG.info("Hello world");
    }
}