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## java.lang
Class Byte

    java.lang.Object
      |
      +--java.lang.Number
            |
            +--java.lang.Byte

All Implemented Interfaces:
  Comparable, Serializable

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`.

Since:
  JDK1.1
See Also:
  `Number`, Serialized Form

Field Summary
`static byte` | `MAX_VALUE` A constant holding the maximum value a `byte` can have, 27-1.
`static byte` | `MIN_VALUE` A constant holding the minimum value a `byte` can have, -27.
`static Class` | `TYPE` The `Class` instance representing the primitive type `byte`.

Constructor Summary
`Byte(byte value)` Constructs a newly allocated `Byte` object that represents the specified `byte` value.
`Byte(String s)` Constructs a newly allocated `Byte` object that represents the `byte` value indicated by the `String` parameter.

Method Summary
`byte` | `byteValue()` Returns the value of this `Byte` as a `byte`.
`int` | `compareTo(Byte anotherByte)` Compares two `Byte` objects numerically.
`int` | `compareTo(Object o)` Compares this `Byte` object to another object.
`static Byte` | `decode(String nm)` Decodes a `String` into a `Byte`.
`double` | `doubleValue()` Returns the value of this `Byte` as a `double`.
`boolean` | `equals(Object obj)` Compares this object to the specified object.
`float` | `floatValue()` Returns the value of this `Byte` as a `float`.
`int` | `hashCode()` Returns a hash code for this `Byte`.
`int` | `intValue()` Returns the value of this `Byte` as an `int`.
`long` | `longValue()` Returns the value of this `Byte` as a `long`.
`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`.
`String` | `toString()` Returns a `String` object representing this `Byte`'s value.
`static String` | `toString(byte b)` Returns a new `String` object representing the specified `byte`.
`static Byte` | `valueOf(String s)` Returns a `Byte` object holding the value given by the specified `String`.
`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.

Methods inherited from class java.lang.Object
`clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

Field Detail

### MIN_VALUE

    public static final byte MIN_VALUE

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

  See Also:
    Constant Field Values

### MAX_VALUE

    public static final byte MAX_VALUE

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

  See Also:
    Constant Field Values

### TYPE

    public static final Class TYPE

  The `Class` instance representing the primitive type `byte`.

Constructor Detail

### 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`.
See Also:
  `parseByte(java.lang.String, int)`

Method Detail

### 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`
  See Also:
    `Integer.toString(int)`

### 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 `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 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 `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 `Character.MIN_RADIX` or larger than `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`.

### 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 `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`.

### 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 `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`.

### 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:
  >   Signopt DecimalNumeral
  >   Signopt `0x` HexDigits
  >   Signopt `0X` HexDigits
  >   Signopt `#` HexDigits
  >   Signopt `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 `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`.
  See Also:
    `parseByte(java.lang.String, int)`

### byteValue

    public byte byteValue()

  Returns the value of this `Byte` as a `byte`.

  Overrides:
    `byteValue` in class `Number`
  Returns:
    the numeric value represented by this object after conversion to type `byte`.

### shortValue

    public short shortValue()

  Returns the value of this `Byte` as a `short`.

  Overrides:
    `shortValue` in class `Number`
  Returns:
    the numeric value represented by this object after conversion to type `short`.

### intValue

    public int intValue()

  Returns the value of this `Byte` as an `int`.

  Specified by:
    `intValue` in class `Number`
  Returns:
    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`.

  Specified by:
    `longValue` in class `Number`
  Returns:
    the numeric value represented by this object after conversion to type `long`.

### floatValue

    public float floatValue()

  Returns the value of this `Byte` as a `float`.

  Specified by:
    `floatValue` in class `Number`
  Returns:
    the numeric value represented by this object after conversion to type `float`.

### doubleValue

    public double doubleValue()

  Returns the value of this `Byte` as a `double`.

  Specified by:
    `doubleValue` in class `Number`
  Returns:
    the numeric value represented by this object after conversion to type `double`.

### 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.

  Overrides:
    `toString` in class `Object`
  Returns:
    a string representation of the value of this object in base 10.

### hashCode

    public int hashCode()

  Returns a hash code for this `Byte`.

  Overrides:
    `hashCode` in class `Object`
  Returns:
    a hash code value for this object.
  See Also:
    `Object.equals(java.lang.Object)`, `Hashtable`

### 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.
  See Also:
    `Object.hashCode()`, `Hashtable`

### 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).
  Since:
    1.2

### compareTo

    public int compareTo(Object o)

  Compares this `Byte` object to another object. If the object is a `Byte`, this function behaves like `compareTo(Byte)`. Otherwise, it throws a `ClassCastException` (as `Byte` objects are only comparable to other `Byte` objects).

  Specified by:
    `compareTo` in interface `Comparable`
  Parameters:
    `o` - the `Object` to be compared.
  Returns:
    the value `0` if the argument is a `Byte` numerically equal to this `Byte`; a value less than `0` if the argument is a `Byte` numerically greater than this `Byte`; and a value greater than `0` if the argument is a `Byte` numerically less than this `Byte`.
  Throws:
    ``ClassCastException`` - if the argument is not a ``Byte``.
  Since:
    1.2
  See Also:
    `Comparable`

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For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2002 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.