com.google.common.primitives
Class SignedBytes

java.lang.Object
  com.google.common.primitives.SignedBytes

public final class SignedBytes
extends Object

Static utility methods pertaining to byte primitives that interpret values as signed. The corresponding methods that treat the values as unsigned are found in UnsignedBytes, and the methods for which signedness is not an issue are in Bytes.

Since:

2009.09.15 tentative

Author:

Kevin Bourrillion

Method Summary

static byte	checkedCast(long value) Returns the byte value that is equal to value, if possible.
static int	compare(byte a, byte b) Compares the two specified byte values.
static String	join(String separator, byte... array) Returns a string containing the supplied byte values separated by separator.
static Comparator<byte[]>	lexicographicalComparator() Returns a comparator that compares two byte arrays lexicographically.
static byte	max(byte... array) Returns the greatest value present in array.
static byte	min(byte... array) Returns the least value present in array.
static byte	saturatedCast(long value) Returns the byte nearest in value to value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

checkedCast

public static byte checkedCast(long value)

Returns the byte value that is equal to value, if possible.

Parameters:

value - any value in the range of the byte type

Returns:

the byte value that equals value

Throws:

IllegalArgumentException - if value is greater than Byte.MAX_VALUE or less than Byte.MIN_VALUE

saturatedCast

public static byte saturatedCast(long value)

Returns the byte nearest in value to value.

Parameters:

value - any long value

Returns:

the same value cast to byte if it is in the range of the byte type, Byte.MAX_VALUE if it is too large, or Byte.MIN_VALUE if it is too small

compare

public static int compare(byte a,
                          byte b)

Compares the two specified byte values. The sign of the value returned is the same as that of ((Byte) a).compareTo(b).

Parameters:

a - the first byte to compare

b - the second byte to compare

Returns:

a negative value if a is less than b; a positive value if a is greater than b; or zero if they are equal

min

public static byte min(byte... array)

Returns the least value present in array.

Parameters:

array - a nonempty array of byte values

Returns:

the value present in array that is less than or equal to every other value in the array

Throws:

IllegalArgumentException - if array is empty

max

public static byte max(byte... array)

Returns the greatest value present in array.

Parameters:

array - a nonempty array of byte values

Returns:

the value present in array that is greater than or equal to every other value in the array

Throws:

IllegalArgumentException - if array is empty

join

public static String join(String separator,
                          byte... array)

Returns a string containing the supplied byte values separated by separator. For example, join(":", 0x01, 0x02, -0x01) returns the string "1:2:-1".

Parameters:

separator - the text that should appear between consecutive values in the resulting string (but not at the start or end)

array - an array of byte values, possibly empty

lexicographicalComparator

public static Comparator<byte[]> lexicographicalComparator()

Returns a comparator that compares two byte arrays lexicographically. That is, it compares, using compare(byte, byte)), the first pair of values that follow any common prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For example, [] < [0x01] < [0x01, 0x80] < [0x01, 0x7F] < [0x02]. Values are treated as signed.

The returned comparator is inconsistent with Object.equals(Object) (since arrays support only identity equality), but it is consistent with Arrays.equals(byte[], byte[]).

Since:

2010.01.04 tentative

See Also:

Lexicographical order article at Wikipedia