Byte
public
final
class
Byte
extends Number
implements
Comparable<Byte>
java.lang.Object | ||
↳ | java.lang.Number | |
↳ | java.lang.Byte |
The Byte
class wraps a value of primitive type byte
in an object. An object of type Byte
contains a single
field whose type is byte
.
In addition, this class provides several methods for converting
a byte
to a String
and a String
to a byte
, as well as other constants and methods useful when dealing
with a byte
.
See also:
Summary
Constants | |
---|---|
int |
BYTES
The number of bytes used to represent a |
byte |
MAX_VALUE
A constant holding the maximum value a |
byte |
MIN_VALUE
A constant holding the minimum value a |
int |
SIZE
The number of bits used to represent a |
Fields | |
---|---|
public
static
final
Class<Byte> |
TYPE
The |
Public constructors | |
---|---|
Byte(byte value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. The static factory
|
|
Byte(String s)
This constructor is deprecated.
It is rarely appropriate to use this constructor.
Use |
Public methods | |
---|---|
byte
|
byteValue()
Returns the value of this |
static
int
|
compare(byte x, byte y)
Compares two |
int
|
compareTo(Byte anotherByte)
Compares two |
static
int
|
compareUnsigned(byte x, byte y)
Compares two |
static
Byte
|
decode(String nm)
Decodes a |
double
|
doubleValue()
Returns the value of this |
boolean
|
equals(Object obj)
Compares this object to the specified object. |
float
|
floatValue()
Returns the value of this |
int
|
hashCode()
Returns a hash code for this |
static
int
|
hashCode(byte value)
Returns a hash code for a |
int
|
intValue()
Returns the value of this |
long
|
longValue()
Returns the value of this |
static
byte
|
parseByte(String s)
Parses the string argument as a signed decimal |
static
byte
|
parseByte(String s, int radix)
Parses the string argument as a signed |
short
|
shortValue()
Returns the value of this |
String
|
toString()
Returns a |
static
String
|
toString(byte b)
Returns a new |
static
int
|
toUnsignedInt(byte x)
Converts the argument to an |
static
long
|
toUnsignedLong(byte x)
Converts the argument to a |
static
Byte
|
valueOf(String s)
Returns a |
static
Byte
|
valueOf(String s, int radix)
Returns a |
static
Byte
|
valueOf(byte b)
Returns a |
Inherited methods | |
---|---|
Constants
BYTES
public static final int BYTES
The number of bytes used to represent a byte
value in two's
complement binary form.
Constant Value: 1 (0x00000001)
MAX_VALUE
public static final byte MAX_VALUE
A constant holding the maximum value a byte
can
have, 27-1.
Constant Value: 127 (0x0000007f)
MIN_VALUE
public static final byte MIN_VALUE
A constant holding the minimum value a byte
can
have, -27.
Constant Value: -128 (0xffffff80)
SIZE
public static final int SIZE
The number of bits used to represent a byte
value in two's
complement binary form.
Constant Value: 8 (0x00000008)
Fields
TYPE
public static final Class<Byte> TYPE
The Class
instance representing the primitive type
byte
.
Public constructors
Byte
public Byte (byte value)
This constructor is deprecated.
It is rarely appropriate to use this constructor. The static factory
valueOf(byte)
is generally a better choice, as it is
likely to yield significantly better space and time performance.
Constructs a newly allocated Byte
object that
represents the specified byte
value.
Parameters | |
---|---|
value |
byte : the value to be represented by the
Byte . |
Byte
public Byte (String s)
This constructor is deprecated.
It is rarely appropriate to use this constructor.
Use parseByte(java.lang.String)
to convert a string to a
byte
primitive, or use valueOf(java.lang.String)
to convert a string to a Byte
object.
Constructs a newly allocated Byte
object that
represents the byte
value indicated by the
String
parameter. The string is converted to a
byte
value in exactly the manner used by the
parseByte
method for radix 10.
Parameters | |
---|---|
s |
String : the String to be converted to a
Byte |
Throws | |
---|---|
NumberFormatException |
if the String
does not contain a parsable byte . |
Public methods
byteValue
public byte byteValue ()
Returns the value of this Byte
as a
byte
.
Returns | |
---|---|
byte |
the numeric value represented by this object after conversion
to type byte . |
compare
public static int compare (byte x, byte y)
Compares two byte
values numerically.
The value returned is identical to what would be returned by:
Byte.valueOf(x).compareTo(Byte.valueOf(y))
Parameters | |
---|---|
x |
byte : the first byte to compare |
y |
byte : the second byte to compare |
Returns | |
---|---|
int |
the value 0 if x == y ;
a value less than 0 if x < y ; and
a value greater than 0 if x > y |
compareTo
public int compareTo (Byte anotherByte)
Compares two Byte
objects numerically.
Parameters | |
---|---|
anotherByte |
Byte : the Byte to be compared. |
Returns | |
---|---|
int |
the value 0 if this Byte is
equal to the argument Byte ; a value less than
0 if this Byte is numerically less
than the argument Byte ; and a value greater than
0 if this Byte is numerically
greater than the argument Byte (signed
comparison). |
compareUnsigned
public static int compareUnsigned (byte x, byte y)
Compares two byte
values numerically treating the values
as unsigned.
Parameters | |
---|---|
x |
byte : the first byte to compare |
y |
byte : the second byte to compare |
Returns | |
---|---|
int |
the value 0 if x == y ; a value less
than 0 if x < y as unsigned values; and
a value greater than 0 if x > y as
unsigned values |
decode
public static Byte decode (String nm)
Decodes a String
into a Byte
.
Accepts decimal, hexadecimal, and octal numbers given by
the following grammar:
DecimalNumeral, HexDigits, and OctalDigits are as defined in section {@jls 3.10.1} of The Java Language Specification, except that underscores are not accepted between digits.
- DecodableString:
- Signopt DecimalNumeral
- Signopt
0x
HexDigits- Signopt
0X
HexDigits- Signopt
#
HexDigits- Signopt
0
OctalDigits- Sign:
-
+
The sequence of characters following an optional
sign and/or radix specifier ("0x
", "0X
",
"#
", or leading zero) is parsed as by the Byte.parseByte
method with the indicated radix (10, 16, or 8).
This sequence of characters must represent a positive value or
a NumberFormatException
will be thrown. The result is
negated if first character of the specified String
is
the minus sign. No whitespace characters are permitted in the
String
.
Parameters | |
---|---|
nm |
String : the String to decode. |
Returns | |
---|---|
Byte |
a Byte object holding the byte
value represented by nm |
Throws | |
---|---|
NumberFormatException |
if the String does not
contain a parsable byte . |
See also:
doubleValue
public double doubleValue ()
Returns the value of this Byte
as a double
after a widening primitive conversion.
Returns | |
---|---|
double |
the numeric value represented by this object after conversion
to type double . |
equals
public boolean equals (Object obj)
Compares this object to the specified object. The result is
true
if and only if the argument is not
null
and is a Byte
object that
contains the same byte
value as this object.
Parameters | |
---|---|
obj |
Object : the object to compare with |
Returns | |
---|---|
boolean |
true if the objects are the same;
false otherwise. |
floatValue
public float floatValue ()
Returns the value of this Byte
as a float
after
a widening primitive conversion.
Returns | |
---|---|
float |
the numeric value represented by this object after conversion
to type float . |
hashCode
public int hashCode ()
Returns a hash code for this Byte
; equal to the result
of invoking intValue()
.
Returns | |
---|---|
int |
a hash code value for this Byte |
hashCode
public static int hashCode (byte value)
Returns a hash code for a byte
value; compatible with
Byte.hashCode()
.
Parameters | |
---|---|
value |
byte : the value to hash |
Returns | |
---|---|
int |
a hash code value for a byte value. |
intValue
public int intValue ()
Returns the value of this Byte
as an int
after
a widening primitive conversion.
Returns | |
---|---|
int |
the numeric value represented by this object after conversion
to type int . |
longValue
public long longValue ()
Returns the value of this Byte
as a long
after
a widening primitive conversion.
Returns | |
---|---|
long |
the numeric value represented by this object after conversion
to type long . |
parseByte
public static byte parseByte (String s)
Parses the string argument as a signed decimal byte
. The characters in the string must all be decimal digits,
except that the first character may be an ASCII minus sign
'-'
('\u002D'
) to indicate a negative
value or an ASCII plus sign '+'
('\u002B'
) to indicate a positive value. The
resulting byte
value is returned, exactly as if the
argument and the radix 10 were given as arguments to the parseByte(java.lang.String, int)
method.
Parameters | |
---|---|
s |
String : a String containing the
byte representation to be parsed |
Returns | |
---|---|
byte |
the byte value represented by the
argument in decimal |
Throws | |
---|---|
NumberFormatException |
if the string does not
contain a parsable byte . |
parseByte
public static byte parseByte (String s, int radix)
Parses the string argument as a signed byte
in the
radix specified by the second argument. The characters in the
string must all be digits, of the specified radix (as
determined by whether Character.digit(char, int)
returns a nonnegative value) except that the first
character may be an ASCII minus sign '-'
('\u002D'
) to indicate a negative value or an
ASCII plus sign '+'
('\u002B'
) to
indicate a positive value. The resulting byte
value is
returned.
An exception of type NumberFormatException
is
thrown if any of the following situations occurs:
- The first argument is
null
or is a string of length zero. - The radix is either smaller than
Character.MIN_RADIX
or larger thanCharacter.MAX_RADIX
. - Any character of the string is not a digit of the
specified radix, except that the first character may be a minus
sign
'-'
('\u002D'
) or plus sign'+'
('\u002B'
) provided that the string is longer than length 1. - The value represented by the string is not a value of type
byte
.
Parameters | |
---|---|
s |
String : the String containing the
byte
representation to be parsed |
radix |
int : the radix to be used while parsing s |
Returns | |
---|---|
byte |
the byte value represented by the string
argument in the specified radix |
Throws | |
---|---|
NumberFormatException |
If the string does
not contain a parsable byte . |
shortValue
public short shortValue ()
Returns the value of this Byte
as a short
after
a widening primitive conversion.
Returns | |
---|---|
short |
the numeric value represented by this object after conversion
to type short . |
toString
public String toString ()
Returns a String
object representing this
Byte
's value. The value is converted to signed
decimal representation and returned as a string, exactly as if
the byte
value were given as an argument to the
toString(byte)
method.
Returns | |
---|---|
String |
a string representation of the value of this object in base 10. |
toString
public static String toString (byte b)
Returns a new String
object representing the
specified byte
. The radix is assumed to be 10.
Parameters | |
---|---|
b |
byte : the byte to be converted |
Returns | |
---|---|
String |
the string representation of the specified byte |
See also:
toUnsignedInt
public static int toUnsignedInt (byte x)
Converts the argument to an int
by an unsigned
conversion. In an unsigned conversion to an int
, the
high-order 24 bits of the int
are zero and the
low-order 8 bits are equal to the bits of the byte
argument.
Consequently, zero and positive byte
values are mapped
to a numerically equal int
value and negative byte
values are mapped to an int
value equal to the
input plus 28.
Parameters | |
---|---|
x |
byte : the value to convert to an unsigned int |
Returns | |
---|---|
int |
the argument converted to int by an unsigned
conversion |
toUnsignedLong
public static long toUnsignedLong (byte x)
Converts the argument to a long
by an unsigned
conversion. In an unsigned conversion to a long
, the
high-order 56 bits of the long
are zero and the
low-order 8 bits are equal to the bits of the byte
argument.
Consequently, zero and positive byte
values are mapped
to a numerically equal long
value and negative byte
values are mapped to a long
value equal to the
input plus 28.
Parameters | |
---|---|
x |
byte : the value to convert to an unsigned long |
Returns | |
---|---|
long |
the argument converted to long by an unsigned
conversion |
valueOf
public static Byte valueOf (String s)
Returns a Byte
object holding the value
given by the specified String
. The argument is
interpreted as representing a signed decimal byte
,
exactly as if the argument were given to the parseByte(java.lang.String)
method. The result is a
Byte
object that represents the byte
value specified by the string.
In other words, this method returns a Byte
object
equal to the value of:
new Byte(Byte.parseByte(s))
Parameters | |
---|---|
s |
String : the string to be parsed |
Returns | |
---|---|
Byte |
a Byte object holding the value
represented by the string argument |
Throws | |
---|---|
NumberFormatException |
If the String does
not contain a parsable byte . |
valueOf
public static Byte valueOf (String s, int radix)
Returns a Byte
object holding the value
extracted from the specified String
when parsed
with the radix given by the second argument. The first argument
is interpreted as representing a signed byte
in
the radix specified by the second argument, exactly as if the
argument were given to the parseByte(java.lang.String, int)
method. The result is a Byte
object that
represents the byte
value specified by the string.
In other words, this method returns a Byte
object
equal to the value of:
new Byte(Byte.parseByte(s, radix))
Parameters | |
---|---|
s |
String : the string to be parsed |
radix |
int : the radix to be used in interpreting s |
Returns | |
---|---|
Byte |
a Byte object holding the value
represented by the string argument in the
specified radix. |
Throws | |
---|---|
NumberFormatException |
If the String does
not contain a parsable byte . |
valueOf
public static Byte valueOf (byte b)
Returns a Byte
instance representing the specified
byte
value.
If a new Byte
instance is not required, this method
should generally be used in preference to the constructor
Byte(byte)
, as this method is likely to yield
significantly better space and time performance since
all byte values are cached.
Parameters | |
---|---|
b |
byte : a byte value. |
Returns | |
---|---|
Byte |
a Byte instance representing b . |