@ImportTestcontainers doesn't work with AOT

[nosan]

#42875

Since Bean's InstanceSupplier cannot be used during the AOT process, I added BeanRegistrationAotProcessor to replace it.

If a container's field is inaccessible, the generated code will be:

@Generated
public class GraalmavenApplicationTests__TestContext001_BeanDefinitions {

	/**
	 * Get the bean instance for 'importTestContainer.task.graalmaven.GraalmavenApplicationTests.mongoDbContainer'.
	 */
	private static MongoDBContainer getMongoDbContainerInstance() {
		try {
			Class<?> clazz = ClassUtils.forName("task.graalmaven.GraalmavenApplicationTests",
					GraalmavenApplicationTests__TestContext001_BeanDefinitions.class.getClassLoader());
			Field field = ReflectionUtils.findField(clazz, "mongoDbContainer");
			Assert.notNull(field, "Field 'mongoDbContainer' is not found");
			ReflectionUtils.makeAccessible(field);
			Object container = ReflectionUtils.getField(field, null);
			Assert.notNull(container, "Container field 'mongoDbContainer' must not have a null value");
			return (MongoDBContainer) container;
		} catch (ClassNotFoundException ex) {
			throw new RuntimeException(ex);
		}
	}

	/**
	 * Get the bean definition for 'mongoDbContainer'.
	 */
	public static BeanDefinition getMongoDbContainerBeanDefinition() {
		RootBeanDefinition beanDefinition = new RootBeanDefinition(MongoDBContainer.class);
		beanDefinition.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
		beanDefinition.setInstanceSupplier(
				GraalmavenApplicationTests__TestContext001_BeanDefinitions::getMongoDbContainerInstance);
		return beanDefinition;
	}

}

If a container's field is accessible, the generated code will be:

@Generated
public class GraalmavenApplicationTests__TestContext001_BeanDefinitions {
  /**
   * Get the bean definition for 'mongoDbContainer'.
   */
  public static BeanDefinition getMongoDbContainerBeanDefinition() {
    RootBeanDefinition beanDefinition = new RootBeanDefinition(MyContainer.class);
    beanDefinition.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
    beanDefinition.setInstanceSupplier(() -> GraalmavenApplicationTests.mongoDbContainer);
    return beanDefinition;
  }
}

An alternative way is FactoryBean instead of InstanceSupplier.

The target branch is 3.2.x

[nosan]

Unfortunately, handling the bean instance supplier for container fields only addresses
half of the issue. The more problematic part involves handling @DynamicPropertySource
methods. These @DynamicPropertySource methods need to be generated and invoked within
the AOT environment. To achieve this, I introduced
DynamicPropertySourceBeanFactoryInitializationAotProcessor

[nosan]

@philwebb
Could I kindly ask you to do a quick review of this PR, and let me know if I'm in the right direction?

[philwebb]

Sorry for the delay @nosan, I haven't had the chance to look in detail at this one yet.

[nosan]

@philwebb
No worries! I completely understand that you’ve been focusing on higher-priority tasks.

[nosan]

I am closing this PR as it is incompatible with versions 3.4.x and 3.5.x due to changes
related to DynamicPropertyRegistrar (DynamicPropertySourceMethodsImporter).

Although this PR might potentially address issues in 3.3.x, it is no longer applicable to 3.4.x and beyond.