equals(…) and equalsIgnoreCase(…)

Question

Why do we have equals() and equalsIgnoreCase() as two different methods, when equals() could have been overloaded with a special

Answer 1

The method equals() is inherited from Object, so its signature should not be changed. equals() can often be used without actually knowing the concrete class of the object, e.g. when iterating through a collection of objects (especially before Java 5 generics). So then you wouldn't even see the other equals() without downcasting your object to String first.

This was a design choice from the creators of Java to make the idiom of using equals() usable exactly the same way for all objects.

Moreover, IMO

if (string1.equalsIgnoreCase(string2)) ...

is more readable, thus less error-prone than

if (string1.equals(string2, true)) ...

Of course, in your own classes you are free to add an equals() with different signature (on top of the standard equals(), that is).