Bad Smells: Bloaters

The bloaters that we can find within a class are:

• Comments
• Long Method
• Large Class
• Long Parameter List

Comments

To do

• When a comment explains a block of code, it uses Extract Method to encapsulate said block of code and provide semantics. The comment usually suggests a name for the method.
• When a comment explains what a method does better than the method name itself, use Rename Method and use the base of the comment to give it a better name.
• When a comment explains preconditions, consider using Enter Assertion to replace the comment with code.

Rewards

• Improves communication.
• May expose duplicity.

Contraindications

Don’t delete comments that explain why something is done a certain way.

Long Method

To do

• Use Extract Method to break the method into smaller portions. Look for comments and white space that separate interesting blocks. Extract methods that have semantic meaning, not just a random chunk of code.
• You may find other refactorings (cleaning up lines, conditionals, and variable usage) that are useful before you start separating the method.

Rewards

• Improves communication.
• May expose duplicity.
• It usually helps the emergence of new classes and abstractions.

Contraindications

Sometimes a long method may be the best way to express something.

Large Class

To do

• Use Extract Class if you can identify a new class that has some of the responsibilities of the current class.
• Use Extract Subclass if you can split responsibilities between the class and a new subclass.
• Use Extract Interface if you can identify a subset of features used by clients of the class.

Rewards

• Improves communication.
• May expose duplicity.

Long Parameter List

To do

• If the parameter value can be replaced from another object that already knows it, use Replace Parameter with Method.
• If the parameter comes from a single object, try Preserve Whole Object.
• If the data does not come from a logical object, you may want to group it using Enter Parameter Object.

Rewards

• Improves communication.
• May expose duplicity.
• Usually reduces the size.

Contraindications

• Sometimes you want to avoid a dependency between two classes.
• Sometimes parameters do not have a common meaning.