java.lang
class Byte

java.lang.Object java.lang.Number java.lang.Byte

All Implemented Interfaces:

Serializable, Comparable

public final class Byte
extends Number
implements Comparable

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.

MAX_VALUE

public static final byte MAX_VALUE

A constant holding the maximum value a byte can have, 2⁷-1.

MIN_VALUE

public static final byte MIN_VALUE

A constant holding the minimum value a byte can have, -2⁷.

SIZE

public static final int SIZE

The number of bits used to represent a byte value in two's complement binary form.

TYPE

public static final Class TYPE

The Class instance representing the primitive type byte.

Byte

public Byte(byte value)

Constructs a newly allocated Byte object that represents the specified byte value.

Parameters:

value - the value to be represented by the Byte.

Byte

public Byte(String s)
     throws NumberFormatException

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 - the String to be converted to a Byte

Throws:

NumberFormatException - If the String does not contain a parsable byte.

byteValue

public byte byteValue()

Returns the value of this Byte as a byte.

Overrides:

byteValue in class Number

compareTo

public int compareTo(Byte anotherByte)

Compares two Byte objects numerically.

Parameters:

anotherByte - the Byte to be compared.

Returns:

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).

decode

public static Byte decode(String nm)
                   throws NumberFormatException

Decodes a String into a Byte. Accepts decimal, hexadecimal, and octal numbers given by the following grammar:

DecodableString:

Sign_opt DecimalNumeral

Sign_opt 0x HexDigits

Sign_opt 0X HexDigits

Sign_opt # HexDigits

Sign_opt 0 OctalDigits

Sign:

-

DecimalNumeral, HexDigits, and OctalDigits are defined in §3.10.1 of the Java Language Specification.

The sequence of characters following an (optional) negative 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 {@link 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 - the String to decode.

Returns:

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.

Overrides:

doubleValue in class Number

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.

Overrides:

equals in class Object

Parameters:

obj - the object to compare with

Returns:

true if the objects are the same; false otherwise.

floatValue

public float floatValue()

Returns the value of this Byte as a float.

Overrides:

floatValue in class Number

hashCode

public int hashCode()

Returns a hash code for this Byte.

Overrides:

hashCode in class Object

intValue

public int intValue()

Returns the value of this Byte as an int.

Overrides:

intValue in class Number

longValue

public long longValue()

Returns the value of this Byte as a long.

Overrides:

longValue in class Number

parseByte

public static byte parseByte(String s)
                      throws NumberFormatException

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. The resulting byte value is returned, exactly as if the argument and the radix 10 were given as arguments to the {@link #parseByte(java.lang.String, int)} method.

Parameters:

s - a String containing the byte representation to be parsed

Returns:

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)
                      throws NumberFormatException

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 {@link java.lang.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. 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 {@link java.lang.Character#MIN_RADIX} or larger than {@link java.lang.Character#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') provided that the string is longer than length 1.
• The value represented by the string is not a value of type byte.

Parameters:

s - the String containing the byte representation to be parsed

radix - the radix to be used while parsing s

Returns:

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.

Overrides:

shortValue in class Number

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 {@link java.lang.Byte#toString(byte)} method.

Overrides:

toString in class Object

Returns:

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 - the byte to be converted

Returns:

the string representation of the specified 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 {@link #Byte(byte)}, as this method is likely to yield significantly better space and time performance by caching frequently requested values.

Parameters:

b - a byte value.

Returns:

a Byte instance representing b.

valueOf

public static Byte valueOf(String s)
                    throws NumberFormatException

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 {@link #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 - the string to be parsed

Returns:

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)
                    throws NumberFormatException

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 {@link #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 - the string to be parsed

radix - the radix to be used in interpreting s

Returns:

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.