Any reason to prefer getClass() over instanceof when generating .equals()?

by

I’m using Eclipse to generate .equals() and .hashCode(), and there is an option labeled “Use ‘instanceof’ to compare types”. The default is for this option to be unchecked and use .getClass() to compare types. Is there any reason I should prefer .getClass() over instanceof?

Without using instanceof:

if (obj == null)
  return false;
if (getClass() != obj.getClass())
  return false;

Using instanceof:

if (obj == null)
  return false;
if (!(obj instanceof MyClass))
  return false;

I usually check the instanceof option, and then go in and remove the “if (obj == null)” check. (It is redundant since null objects will always fail instanceof.) Is there any reason that’s a bad idea?

11 Answers
11

Leave a Comment