Byte | Android Developers (original) (raw)

public final class Byte
`` extends [Number](/reference/java/lang/Number) implements[Comparable](/reference/java/lang/Comparable)<[Byte](/reference/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.

Summary

Constants
int	BYTES The number of bytes used to represent a byte value in two's complement binary form.
byte	MAX_VALUE A constant holding the maximum value a byte can have, 27-1.
byte	MIN_VALUE A constant holding the minimum value a byte can have, -27.
int	SIZE The number of bits used to represent a byte value in two's complement binary form.

Fields
public static finalClass<Byte>	TYPE The Class instance representing the primitive typebyte.

Public constructors
Byte(byte value) This constructor is deprecated. It is rarely appropriate to use this constructor. The static factoryvalueOf(byte) is generally a better choice, as it is likely to yield significantly better space and time performance.
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 abyte primitive, or use valueOf(java.lang.String) to convert a string to a Byte object.

Public methods
byte	byteValue() Returns the value of this Byte as abyte.
static int	compare(byte x, byte y) Compares two byte values numerically.
int	compareTo(Byte anotherByte) Compares two Byte objects numerically.
static int	compareUnsigned(byte x, byte y) Compares two byte values numerically treating the values as unsigned.
staticByte	decode(String nm) Decodes a String into a Byte.
double	doubleValue() Returns the value of this Byte as a double after a widening primitive conversion.
boolean	equals(Object obj) Compares this object to the specified object.
float	floatValue() Returns the value of this Byte as a float after a widening primitive conversion.
int	hashCode() Returns a hash code for this Byte; equal to the result of invoking intValue().
static int	hashCode(byte value) Returns a hash code for a byte value; compatible withByte.hashCode().
int	intValue() Returns the value of this Byte as an int after a widening primitive conversion.
long	longValue() Returns the value of this Byte as a long after a widening primitive conversion.
static byte	parseByte(String s) Parses the string argument as a signed decimal byte.
static byte	parseByte(String s, int radix) Parses the string argument as a signed byte in the radix specified by the second argument.
short	shortValue() Returns the value of this Byte as a short after a widening primitive conversion.
String	toString() Returns a String object representing thisByte's value.
staticString	toString(byte b) Returns a new String object representing the specified byte.
static int	toUnsignedInt(byte x) Converts the argument to an int by an unsigned conversion.
static long	toUnsignedLong(byte x) Converts the argument to a long by an unsigned conversion.
staticByte	valueOf(String s) Returns a Byte object holding the value given by the specified String.
staticByte	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.
staticByte	valueOf(byte b) Returns a Byte instance representing the specifiedbyte value.

Inherited methods
From class java.lang.Number byte byteValue() Returns the value of the specified number as a byte. abstract double doubleValue() Returns the value of the specified number as a double. abstract float floatValue() Returns the value of the specified number as a float. abstract int intValue() Returns the value of the specified number as an int. abstract long longValue() Returns the value of the specified number as a long. short shortValue() Returns the value of the specified number as a short.
From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. finalClass<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
From interface java.lang.Comparable abstract int compareTo(Byte o) Compares this object with the specified object for order.

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 typebyte.

Public constructors

Byte

public Byte (byte value)

This constructor is deprecated.
It is rarely appropriate to use this constructor. The static factory[valueOf(byte)](/reference/java/lang/Byte#valueOf%28byte%29) 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 theByte.

Byte

public Byte (String s)

This constructor is deprecated.
It is rarely appropriate to use this constructor. Use [parseByte(java.lang.String)](/reference/java/lang/Byte#parseByte%28java.lang.String%29) to convert a string to abyte primitive, or use [valueOf(java.lang.String)](/reference/java/lang/Byte#valueOf%28java.lang.String%29) to convert a string to a Byte object.

Constructs a newly allocated Byte object that represents the byte value indicated by theString parameter. The string is converted to abyte value in exactly the manner used by theparseByte method for radix 10.

Parameters
s	String: the String to be converted to aByte

Throws
NumberFormatException	if the String does not contain a parsable byte.

Public methods

byteValue

public byte byteValue ()

Returns the value of this Byte as abyte.

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 than0 if this Byte is numerically less than the argument Byte; and a value greater than0 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:

DecodableString:

Signopt DecimalNumeral

Signopt 0x HexDigits

Signopt 0X HexDigits

Signopt # HexDigits

Signopt 0 OctalDigits

Sign:

-

+

DecimalNumeral, HexDigits, and OctalDigits are as defined in section {@jls 3.10.1} ofThe Java Language Specification, except that underscores are not accepted between digits.

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](/reference/java/lang/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 theString.

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.

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 istrue if and only if the argument is notnull 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 withByte.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)](/reference/java/lang/Byte#parseByte%28java.lang.String,%20int%29) method.

Parameters
s	String: a String containing thebyte 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)](/reference/java/lang/Character#digit%28char,%20int%29) 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](/reference/java/lang/Character#MIN%5FRADIX) or larger than [Character.MAX_RADIX](/reference/java/lang/Character#MAX%5FRADIX).
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 typebyte.

Parameters
s	String: the String containing thebyte 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 thisByte'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)](/reference/java/lang/Byte#toString%28byte%29) 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

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)](/reference/java/lang/Byte#parseByte%28java.lang.String%29) method. The result is aByte 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)](/reference/java/lang/Byte#parseByte%28java.lang.String,%20int%29) 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 specifiedbyte value. If a new Byte instance is not required, this method should generally be used in preference to the constructor[Byte(byte)](/reference/java/lang/Byte#Byte%28byte%29), 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.