A CharSequence is a readable sequence of char values. This
interface provides uniform, read-only access to many different kinds of
char sequences.
A char value represents a character in the Basic
Multilingual Plane (BMP) or a surrogate. Refer to Unicode Character Representation for details.
This interface does not refine the general contracts of the equals and hashCode methods. The result of comparing two
objects that implement CharSequence is therefore, in general,
undefined. Each object may be implemented by a different class, and there
is no guarantee that each class will be capable of testing its instances
for equality with those of the other. It is therefore inappropriate to use
arbitrary CharSequence instances as elements in a set or as keys in
a map.
@spec JSR-51