@GwtCompatible(emulated=true) public final class Chars extends Object
char primitives, that are not already found in
either Character or Arrays.
All the operations in this class treat char values strictly numerically; they are
neither Unicode-aware nor locale-dependent.
See the Guava User Guide article on primitive utilities.
| Modifier and Type | Field and Description |
|---|---|
static int |
BYTES
The number of bytes required to represent a primitive
char value. |
| Modifier and Type | Method and Description |
|---|---|
static List<Character> |
asList(char... backingArray)
Returns a fixed-size list backed by the specified array, similar to
Arrays.asList(Object[]). |
static char |
checkedCast(long value)
Returns the
char value that is equal to value, if possible. |
static int |
compare(char a,
char b)
Compares the two specified
char values. |
static char[] |
concat(char[]... arrays)
Returns the values from each provided array combined into a single array.
|
static char |
constrainToRange(char value,
char min,
char max)
Returns the value nearest to
value which is within the closed range [min..max]. |
static boolean |
contains(char[] array,
char target)
Returns
true if target is present as an element anywhere in array. |
static char[] |
ensureCapacity(char[] array,
int minLength,
int padding)
Returns an array containing the same values as
array, but guaranteed to be of a
specified minimum length. |
static char |
fromByteArray(byte[] bytes)
Returns the
char value whose big-endian representation is stored in the first 2 bytes
of bytes; equivalent to ByteBuffer.wrap(bytes).getChar(). |
static char |
fromBytes(byte b1,
byte b2)
Returns the
char value whose byte representation is the given 2 bytes, in big-endian
order; equivalent to Chars.fromByteArray(new byte[] {b1, b2}). |
static int |
hashCode(char value)
Returns a hash code for
value; equal to the result of invoking
((Character) value).hashCode(). |
static int |
indexOf(char[] array,
char target)
Returns the index of the first appearance of the value
target in array. |
static int |
indexOf(char[] array,
char[] target)
Returns the start position of the first occurrence of the specified
target within array, or -1 if there is no such occurrence. |
static String |
join(String separator,
char... array)
Returns a string containing the supplied
char values separated by separator. |
static int |
lastIndexOf(char[] array,
char target)
Returns the index of the last appearance of the value
target in array. |
static Comparator<char[]> |
lexicographicalComparator()
Returns a comparator that compares two
char arrays lexicographically. |
static char |
max(char... array)
Returns the greatest value present in
array. |
static char |
min(char... array)
Returns the least value present in
array. |
static char |
saturatedCast(long value)
Returns the
char nearest in value to value. |
static char[] |
toArray(Collection<Character> collection)
Copies a collection of
Character instances into a new array of primitive char
values. |
static byte[] |
toByteArray(char value)
Returns a big-endian representation of
value in a 2-element byte array; equivalent to
ByteBuffer.allocate(2).putChar(value).array(). |
public static final int BYTES
char value.
Java 8 users: use Character.BYTES instead.
public static int hashCode(char value)
value; equal to the result of invoking
((Character) value).hashCode().
Java 8 users: use Character.hashCode(char) instead.
value - a primitive char valuepublic static char checkedCast(long value)
char value that is equal to value, if possible.value - any value in the range of the char typechar value that equals valueIllegalArgumentException - if value is greater than Character.MAX_VALUE
or less than Character.MIN_VALUEpublic static char saturatedCast(long value)
char nearest in value to value.value - any long valuechar if it is in the range of the char type,
Character.MAX_VALUE if it is too large, or Character.MIN_VALUE if it is too
smallpublic static int compare(char a, char b)
char values. The sign of the value returned is the same as
that of ((Character) a).compareTo(b).
Note for Java 7 and later: this method should be treated as deprecated; use the
equivalent Character.compare(char, char) method instead.
a - the first char to compareb - the second char to comparea is less than b; a positive value if a is
greater than b; or zero if they are equalpublic static boolean contains(char[] array, char target)
true if target is present as an element anywhere in array.array - an array of char values, possibly emptytarget - a primitive char valuetrue if array[i] == target for some value of ipublic static int indexOf(char[] array, char target)
target in array.array - an array of char values, possibly emptytarget - a primitive char valuei for which array[i] == target, or -1 if no
such index exists.public static int indexOf(char[] array, char[] target)
target within array, or -1 if there is no such occurrence.
More formally, returns the lowest index i such that
Arrays.copyOfRange(array, i, i + target.length) contains exactly the same elements as
target.
array - the array to search for the sequence targettarget - the array to search for as a sub-sequence of arraypublic static int lastIndexOf(char[] array, char target)
target in array.array - an array of char values, possibly emptytarget - a primitive char valuei for which array[i] == target, or -1 if no
such index exists.public static char min(char... array)
array.array - a nonempty array of char valuesarray that is less than or equal to every other value in
the arrayIllegalArgumentException - if array is emptypublic static char max(char... array)
array.array - a nonempty array of char valuesarray that is greater than or equal to every other value
in the arrayIllegalArgumentException - if array is empty@Beta public static char constrainToRange(char value, char min, char max)
value which is within the closed range [min..max].
If value is within the range [min..max], value is returned
unchanged. If value is less than min, min is returned, and if
value is greater than max, max is returned.
value - the char value to constrainmin - the lower bound (inclusive) of the range to constrain value tomax - the upper bound (inclusive) of the range to constrain value toIllegalArgumentException - if min > maxpublic static char[] concat(char[]... arrays)
concat(new char[] {a, b}, new char[] {}, new char[] {c} returns the array
{a, b, c}.arrays - zero or more char arrays@GwtIncompatible public static byte[] toByteArray(char value)
value in a 2-element byte array; equivalent to
ByteBuffer.allocate(2).putChar(value).array(). For example, the input value
'\\u5432' would yield the byte array {0x54, 0x32}.
If you need to convert and concatenate several values (possibly even of different types),
use a shared ByteBuffer instance, or use
ByteStreams.newDataOutput() to get a growable buffer.
@GwtIncompatible public static char fromByteArray(byte[] bytes)
char value whose big-endian representation is stored in the first 2 bytes
of bytes; equivalent to ByteBuffer.wrap(bytes).getChar(). For example, the
input byte array {0x54, 0x32} would yield the char value '\\u5432'.
Arguably, it's preferable to use ByteBuffer; that library exposes much more
flexibility at little cost in readability.
IllegalArgumentException - if bytes has fewer than 2 elements@GwtIncompatible public static char fromBytes(byte b1, byte b2)
char value whose byte representation is the given 2 bytes, in big-endian
order; equivalent to Chars.fromByteArray(new byte[] {b1, b2}).public static char[] ensureCapacity(char[] array, int minLength, int padding)
array, but guaranteed to be of a
specified minimum length. If array already has a length of at least minLength,
it is returned directly. Otherwise, a new array of size minLength + padding is
returned, containing the values of array, and zeroes in the remaining places.array - the source arrayminLength - the minimum length the returned array must guaranteepadding - an extra amount to "grow" the array by if growth is necessaryarray, with guaranteed minimum length
minLengthIllegalArgumentException - if minLength or padding is negativepublic static String join(String separator, char... array)
char values separated by separator.
For example, join("-", '1', '2', '3') returns the string "1-2-3".separator - the text that should appear between consecutive values in the resulting string
(but not at the start or end)array - an array of char values, possibly emptypublic static Comparator<char[]> lexicographicalComparator()
char arrays lexicographically. That is, it
compares, using compare(char, char)), the first pair of values that follow any common
prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For
example, [] < ['a'] < ['a', 'b'] < ['b'].
The returned comparator is inconsistent with Object.equals(Object) (since arrays
support only identity equality), but it is consistent with
Arrays.equals(char[], char[]).
public static char[] toArray(Collection<Character> collection)
Character instances into a new array of primitive char
values.
Elements are copied from the argument collection as if by collection.toArray(). Calling this method is as thread-safe as calling that method.
collection - a collection of Character objectscollection, in the same order, converted
to primitivesNullPointerException - if collection or any of its elements is nullpublic static List<Character> asList(char... backingArray)
Arrays.asList(Object[]). The list supports List.set(int, Object), but any
attempt to set a value to null will result in a NullPointerException.
The returned list maintains the values, but not the identities, of Character objects
written to or read from it. For example, whether list.get(0) == list.get(0) is true for
the returned list is unspecified.
backingArray - the array to back the listCopyright © 2010-2017. All Rights Reserved.