/* Byte.java -- object wrapper for byte
Copyright (C) 1998, 2001, 2002, 2005 Free Software Foundation, Inc.
This file is part of GNU Classpath.
GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
Linking this library statically or dynamically with other modules is
making a combined work based on this library. Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.
As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module. An independent module is a module which is not derived from
or based on this library. If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so. If you do not wish to do so, delete this
exception statement from your version. */
package java.lang;
/**
* Instances of class Byte
represent primitive byte
* values.
*
* Additionally, this class provides various helper functions and variables
* useful to bytes.
*
* @author Paul Fisher
* @author John Keiser
* @author Per Bothner
* @author Eric Blake (ebb9@email.byu.edu)
* @since 1.1
* @status updated to 1.4
*/
public final class Byte extends Number implements Comparable
{
/**
* Compatible with JDK 1.1+.
*/
private static final long serialVersionUID = -7183698231559129828L;
/**
* The minimum value a byte
can represent is -128 (or
* -27).
*/
public static final byte MIN_VALUE = -128;
/**
* The maximum value a byte
can represent is 127 (or
* 27 - 1).
*/
public static final byte MAX_VALUE = 127;
/**
* The primitive type byte
is represented by this
* Class
object.
*/
public static final Class TYPE = VMClassLoader.getPrimitiveClass('B');
/**
* The immutable value of this Byte.
*
* @serial the wrapped byte
*/
private final byte value;
/**
* Create a Byte
object representing the value of the
* byte
argument.
*
* @param value the value to use
*/
public Byte(byte value)
{
this.value = value;
}
/**
* Create a Byte
object representing the value specified
* by the String
argument
*
* @param s the string to convert
* @throws NumberFormatException if the String does not contain a byte
* @see #valueOf(String)
*/
public Byte(String s)
{
value = parseByte(s, 10);
}
/**
* Converts the byte
to a String
and assumes
* a radix of 10.
*
* @param b the byte
to convert to String
* @return the String
representation of the argument
*/
public static String toString(byte b)
{
return String.valueOf(b);
}
/**
* Converts the specified String
into a byte
.
* This function assumes a radix of 10.
*
* @param s the String
to convert
* @return the byte
value of s
* @throws NumberFormatException if s
cannot be parsed as a
* byte
* @see #parseByte(String)
*/
public static byte parseByte(String s)
{
return parseByte(s, 10);
}
/**
* Converts the specified String
into an int
* using the specified radix (base). The string must not be null
* or empty. It may begin with an optional '-', which will negate the answer,
* provided that there are also valid digits. Each digit is parsed as if by
* Character.digit(d, radix)
, and must be in the range
* 0
to radix - 1
. Finally, the result must be
* within MIN_VALUE
to MAX_VALUE
, inclusive.
* Unlike Double.parseDouble, you may not have a leading '+'.
*
* @param s the String
to convert
* @param radix the radix (base) to use in the conversion
* @return the String
argument converted to byte
* @throws NumberFormatException if s
cannot be parsed as a
* byte
*/
public static byte parseByte(String s, int radix)
{
int i = Integer.parseInt(s, radix, false);
if ((byte) i != i)
throw new NumberFormatException();
return (byte) i;
}
/**
* Creates a new Byte
object using the String
* and specified radix (base).
*
* @param s the String
to convert
* @param radix the radix (base) to convert with
* @return the new Byte
* @throws NumberFormatException if s
cannot be parsed as a
* byte
* @see #parseByte(String, int)
*/
public static Byte valueOf(String s, int radix)
{
return new Byte(parseByte(s, radix));
}
/**
* Creates a new Byte
object using the String
,
* assuming a radix of 10.
*
* @param s the String
to convert
* @return the new Byte
* @throws NumberFormatException if s
cannot be parsed as a
* byte
* @see #Byte(String)
* @see #parseByte(String)
*/
public static Byte valueOf(String s)
{
return new Byte(parseByte(s, 10));
}
/**
* Convert the specified String
into a Byte
.
* The String
may represent decimal, hexadecimal, or
* octal numbers.
*
*
The extended BNF grammar is as follows:
*
* DecodableString: * ( [* Finally, the value must be in the range-
] DecimalNumber ) * | ( [-
] (0x
|0X
* |#
) { HexDigit }+ ) * | ( [-
]0
{ OctalDigit } ) * DecimalNumber: * DecimalDigit except '0' { DecimalDigit } * DecimalDigit: * Character.digit(d, 10) has value 0 to 9 * OctalDigit: * Character.digit(d, 8) has value 0 to 7 * DecimalDigit: * Character.digit(d, 16) has value 0 to 15 *
MIN_VALUE
to
* MAX_VALUE
, or an exception is thrown.
*
* @param s the String
to interpret
* @return the value of the String as a Byte
* @throws NumberFormatException if s
cannot be parsed as a
* byte
* @throws NullPointerException if s
is null
* @see Integer#decode(String)
*/
public static Byte decode(String s)
{
int i = Integer.parseInt(s, 10, true);
if ((byte) i != i)
throw new NumberFormatException();
return new Byte((byte) i);
}
/**
* Return the value of this Byte
.
*
* @return the byte value
*/
public byte byteValue()
{
return value;
}
/**
* Return the value of this Byte
as a short
.
*
* @return the short value
*/
public short shortValue()
{
return value;
}
/**
* Return the value of this Byte
as an int
.
*
* @return the int value
*/
public int intValue()
{
return value;
}
/**
* Return the value of this Byte
as a long
.
*
* @return the long value
*/
public long longValue()
{
return value;
}
/**
* Return the value of this Byte
as a float
.
*
* @return the float value
*/
public float floatValue()
{
return value;
}
/**
* Return the value of this Byte
as a double
.
*
* @return the double value
*/
public double doubleValue()
{
return value;
}
/**
* Converts the Byte
value to a String
and
* assumes a radix of 10.
*
* @return the String
representation of this Byte
* @see Integer#toString()
*/
public String toString()
{
return String.valueOf(value);
}
/**
* Return a hashcode representing this Object. Byte
's hash
* code is simply its value.
*
* @return this Object's hash code
*/
public int hashCode()
{
return value;
}
/**
* Returns true
if obj
is an instance of
* Byte
and represents the same byte value.
*
* @param obj the object to compare
* @return whether these Objects are semantically equal
*/
public boolean equals(Object obj)
{
return obj instanceof Byte && value == ((Byte) obj).value;
}
/**
* Compare two Bytes numerically by comparing their byte
values.
* The result is positive if the first is greater, negative if the second
* is greater, and 0 if the two are equal.
*
* @param b the Byte to compare
* @return the comparison
* @since 1.2
*/
public int compareTo(Byte b)
{
return value - b.value;
}
/**
* Behaves like compareTo(Byte)
unless the Object
* is not a Byte
.
*
* @param o the object to compare
* @return the comparison
* @throws ClassCastException if the argument is not a Byte
* @see #compareTo(Byte)
* @see Comparable
* @since 1.2
*/
public int compareTo(Object o)
{
return compareTo((Byte) o);
}
}