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.
char
value at the specified index. An index ranges from zero
to length() - 1. The first char
value of the sequence is at
index zero, the next at index one, and so on, as for array
indexing.
If the char
value specified by the index is a
surrogate, the surrogate
value is returned.
char
s in the sequence.CharSequence
that is a subsequence of this sequence.
The subsequence starts with the char
value at the specified index and
ends with the char
value at index end - 1. The length
(in char
s) of the
returned sequence is end - start, so if start == end
then an empty sequence is returned.