Session about code smells as presented at - EPAM SEC Spring 2014 in June 2014 in Budapest, Hungary - ACE in March 2015 in Krakow, Poland

1. Your Code Smells Too!
Time to Deodorize
Gino Marckx

2. cb pyroclastichawk - https://www.flickr.com/photos/18536761@N00/367669179

3. cb Iwan Gabovitch - https://www.flickr.com/photos/qubodup/4439090296

4. cb Iwan Gabovitch - https://www.flickr.com/photos/qubodup/4438310359

5. CAUTION
BAD ROAD
AHEAD

6. CAUTION
BAD CODE
AHEAD

7. public class Person {
public String m_name;
public String m_street;
public String m_zip;
public String m_city;
public String m_province;
public String m_country;
public Person(String name, String country) { ... }
public Person(String name, String town, String country) { ... }
public Person(String name, String s, String z, String c, String p,
String country) { ... }
public void add(Person person) { ... }
public final List getFriends() { ... }
public double between(Person person) { ... }
public Person closestFriend() { ... }
}

8. The Wallaroo Prints © 2011

9. public class Person {
public String name;
public Address address;
public Person(String name, Address address) { ... }
public void addFriend(Person person) { ... }
public List<Person> getFriends() { ... }
/**
* Find the friend who lives closest.
*
* @return the friend who lives closest
* @throws NoSuchElementException in case this person has no friends
*/
public Person getNearestFriend() { ... }
}

10. • Meaningful names
• Excessive use of literals
• Long parameter list
• Excessively short identifiers
• Feature envy
• Readability
• Maintainability
• Velocity

11. public class Address {
public Address(String country) { ... }
public Address(String city, String country) { ... }
public Address(String street, String postalCode, String city,
String state, String country) { ... }
public String getStreet() { ... }
public String getPostalCode() { ... }
public String getCity() { ... }
public String getState() { ... }
public String getCountry() { ... }
public Point getGeographicalLocation() { ... }
/**
* Calculate the distance in kilometres to another address.
*
* @param anotherAddress the other address to calculate the distance to
* @return the distance in kilometres between this address and the other
* address
* @throws IllegalArgumentException when location of either address is
* unknown
*/
public double distanceTo(Address anotherAddress) { ... }
}

12. http://www.zazzle.ca/comments_a_deodorant_to_mask_code_smells_tshirt-235182622652051339

13. The Wallaroo Prints © 2011

14. public class AddressBuilder {
public AddressBuilder(AddressLocator addressLocator) { ... }
public AddressBuilder() { ... }
public AddressBuilder withCountry(String country) { ... }
public AddressBuilder withStreet(String street) { ... }
public AddressBuilder withCity(String city) { ... }
public AddressBuilder withPostalCode(String postalCode) { ... }
public AddressBuilder withState(String state) { ... }
public Address build() throws UnknownGeographicalLocation { ... }
}
public class Address {
Address(AddressLocator locator, String street, String zipCode,
String city, String state, String country) { ... }
...
public Distance distanceTo(Address anotherAddress) { ... }
}

15. public class AddressTest {
public AddressLocator createMockLocatorWithPolandCentreOfTheUniverse() {
... }
@Test
public void testDistanceTo() throws Throwable {
AddressBuilder builder = new AddressBuilder(
createMockLocatorWithPolandCentreOfTheUniverse());
Address polishAddress = builder.withCountry("Poland").build(),
canadianAddress = builder.withCountry("Canada").build();
assertEquals(new Distance(1000, Distance.Unit.KILOMETRE),
polishAddress.distanceTo(canadianAddress));
}
}

16. • Dependency inversion
• Excessive use of literals
• Long parameter list
• Feature envy
• Testability
• Maintainability
• Velocity

17. Velocity
Testability
Maintainability

18. Build Software
The Right Way
… to be agile

19. Thank you!
Gino Marckx
Director, Agile Competency Center