Dispensables.

A method is filled with explanatory comments.

A data class refers to a class that contains only fields and crude methods for accessing them (getters and setters). These are simply containers for data used by other classes. These classes don’t contain any additional functionality and can’t independently operate on the data that they own.

A variable, parameter, field, method or class is no longer used (usually because it’s obsolete).

Two code fragments look almost identical.

Understanding and maintaining classes always costs time and money. So if a class doesn’t do enough to earn your attention, it should be deleted.

There’s an unused class, method, field or parameter.