public interface CharSequence
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.
| Modifier and Type | Method and Description |
|---|---|
char |
charAt(int index)
Returns the
char value at the specified index. |
default IntStream |
chars()
Returns a stream of
int zero-extending the char values
from this sequence. |
default IntStream |
codePoints()
Returns a stream of code point values from this sequence.
|
int |
length()
Returns the length of this character sequence.
|
CharSequence |
subSequence(int start,
int end)
Returns a
CharSequence that is a subsequence of this sequence. |
String |
toString()
Returns a string containing the characters in this sequence in the same
order as this sequence.
|
int length()
chars in the sequence.chars in this sequencechar charAt(int index)
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.
index - the index of the char value to be returnedchar valueIndexOutOfBoundsException - if the index argument is negative or not less than
length()CharSequence subSequence(int start, int end)
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 chars) of the
returned sequence is end - start, so if start == end
then an empty sequence is returned.start - the start index, inclusiveend - the end index, exclusiveIndexOutOfBoundsException - if start or end are negative,
if end is greater than length(),
or if start is greater than endString toString()
default IntStream chars()
int zero-extending the char values
from this sequence. Any char which maps to a surrogate code
point is passed through uninterpreted.
If the sequence is mutated while the stream is being read, the result is undefined.
default IntStream codePoints()
int values which are then passed to the stream.
If the sequence is mutated while the stream is being read, the result is undefined.
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For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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