Over the last few decades we've been bombed with anti-pattern warnings carrying ear-appealing neologisms, such as Primitive Obsession, Object Orgy and Feature Envy. This phenomenon is making us live in a constant fear of life-threatening situations. In the act of self-preservation we don't only avoid anti-patterns, but we make sure we drive away from them as far as we possibly could. However, this is 2016 and a lot has changed. Maybe we drove away a bit too far. Let's start an anti movement: anti anti-patterns. In this talk we motivate our theory that some code smells can now safely be reinterpreted and become the astonishing scent of a fabulous ripe cheese.

1. @nickvdh @Hypernation#Devoxx #junior2professional
Anti anti patterns
Nick Vanderhoven
Jeroen Horemans

2. @nickvdh @Hypernation#Devoxx #junior2professional
Anti anti patterns
Nick : The professional with several successful projects
Jeroen : The anti pattern advocate whose project just failed
All code samples are modifications of real code

3. @nickvdh @Hypernation#Devoxx #junior2professional
Anti anti patterns
Nick : The professional with several successful projects
Jeroen : The anti pattern advocate whose project just failed
All code samples are modifications of real code

4. @nickvdh @Hypernation#Devoxx #junior2professional
Big ball of mud
● To avoid this
○ 256 maven modules
○ 6 levels of poms
○ Every bounded context has
■ An Api
■ An enum module
■ A build module
■ A domain module
■ A ...

5. @nickvdh @Hypernation#Devoxx #junior2professional
Big ball of mud
The spaghetti monster
● Try to keep it simple
● Limit your maven structure to the minimum
● Add api modules and others when needed

6. @nickvdh @Hypernation#Devoxx #junior2professional
Primitive obsession
The Customer number
● Elaborate design

7. @nickvdh @Hypernation#Devoxx #junior2professional
Primitive obsession
Primitive Phobia
● The Customer number
○ What did you try to solve?
○ Did it have business logic?
○ Was it easy to refactor?
○ Test creation data hell or heaven

8. @nickvdh @Hypernation#Devoxx #junior2professional
Composition over inheritance
● Composition of the domain model
○ Chihuahua encapsulates dog
○ Dog encapsulates animal
Hundreds lines of code

9. @nickvdh @Hypernation#Devoxx #junior2professional
Composition over inheritance
Animal abuser
Just use the “ is a “ rule

10. @nickvdh @Hypernation#Devoxx #junior2professional
Blind faith
● We went for 100% test coverage
○ Tested every getter, setter, hashcode
○ 2 fulltime devs adding all missing tests

11. @nickvdh @Hypernation#Devoxx #junior2professional
Blind faith
The crazy blind typer
● Even better is to not write the lines yourself
○ Testing is important
○ Test first is even better
○ Don’t overdo it
@Getter
@Builder
@ToString
@EqualsAndHashCode
@AllArgsConstructor
public class Option {
private String label;
private Boolean active;
}

12. @nickvdh @Hypernation#Devoxx #junior2professional
Diaper pattern
● Catched every exception
● Wrapped all exceptions
● Throw it further up

13. @nickvdh @Hypernation#Devoxx #junior2professional
Diaper pattern
Diaper Genie
● Right handling on the right level
● Frameworks can help you (spring)
● In some cases, just let it go
@Override
@SneakyThrows
public Result <T> find(String id) {
List<Account> accounts = repository.find(id);
return accounts;
}

14. @nickvdh @Hypernation#Devoxx #junior2professional
Nih (Not Invented Here)
● Never write your own framework!
○ We did a lot of copy paste
○ Boilerplate FTW ?

15. @nickvdh @Hypernation#Devoxx #junior2professional
Nih (Not Invented Here)
The Boiler Plater
● business value > boilerplate
○ A custom annotation is not a crime
○ Reflection is not evil, but use it wisely
○ Aspects can help you out

16. @nickvdh @Hypernation#Devoxx #junior2professional
Base bean
No god classes on my watch
public class SomeImportantIntegrationTest{
@Rule
public ApplicationLoadingRule applicationRule = new ApplicationLoadingRule ();
@Rule
public RestServiceStubRule restStubRule = new RestServiceStubRule();
@Rule
public DataSourceCreatingRule datasourceRule = new DataSourceCreatingRule();
@Rule
public DataPreparationRule cleanRule = new DataPreparationRule();
@Rule
public DataCreationRule dataRule = new DataCreationRule();
@Rule
public MakeItAllWorkRule workRule = new MakeItAllWorkRule();

17. @nickvdh @Hypernation#Devoxx #junior2professional
Base bean
The anarchist
AbstractIntegrationTest
@RunWith(SpringRunner.class)
public class ImportantIntegrationTest extends AbstractIntegrationTest {

18. @nickvdh @Hypernation#Devoxx #junior2professional
KISS
● Your code should focus on business value anyway
● Anti patterns are not a silver bullet
● As with normal patterns use it wisely
● Let frameworks help you out
● Refactor at the right time

19. @nickvdh @Hypernation#Devoxx #junior2professional
KISS
The anti pattern troll
● Your code should focus on business value anyway.
● Anti patterns are not a silver bullet.
● As with normal patterns use it wisely.
● Let frameworks help you out
● Refactor at the right time

20. @nickvdh @Hypernation#Devoxx #junior2professional
Thank you!
Nick Vanderhoven
Jeroen Horemans