Class UnsignedBytes



  • public final class UnsignedBytes
    extends Object
    Static utility methods pertaining to byte primitives that interpret values as unsigned (that is, any negative value b is treated as the positive value 256 + b). The corresponding methods that treat the values as signed are found in SignedBytes, and the methods for which signedness is not an issue are in Bytes.

    See the Guava User Guide article on primitive utilities.

    Since:
    1.0
    • Field Summary

      Fields

      Modifier and Type Field and Description
      static byte MAX_POWER_OF_TWO
      The largest power of two that can be represented as an unsigned byte.
      static byte MAX_VALUE
      The largest value that fits into an unsigned byte.
    • Method Summary

      Methods

      Modifier and Type Method and Description
      static byte checkedCast(long value)
      Returns the byte value that, when treated as unsigned, is equal to value, if possible.
      static int compare(byte a, byte b)
      Compares the two specified byte values, treating them as unsigned values between 0 and 255 inclusive.
      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 parseUnsignedByte(String string)
      Returns the unsigned byte value represented by the given decimal string.
      static byte parseUnsignedByte(String string, int radix)
      Returns the unsigned byte value represented by a string with the given radix.
      static byte saturatedCast(long value)
      Returns the byte value that, when treated as unsigned, is nearest in value to value.
      static int toInt(byte value)
      Returns the value of the given byte as an integer, when treated as unsigned.
      static String toString(byte x)
      Returns a string representation of x, where x is treated as unsigned.
      static String toString(byte x, int radix)
      Returns a string representation of x for the given radix, where x is treated as unsigned.
    • Field Detail

      • MAX_POWER_OF_TWO

        public static final byte MAX_POWER_OF_TWO
        The largest power of two that can be represented as an unsigned byte.
        Since:
        10.0
        See Also:
        Constant Field Values
      • MAX_VALUE

        public static final byte MAX_VALUE
        The largest value that fits into an unsigned byte.
        Since:
        13.0
        See Also:
        Constant Field Values
    • Method Detail

      • toInt

        public static int toInt(byte value)
        Returns the value of the given byte as an integer, when treated as unsigned. That is, returns value + 256 if value is negative; value itself otherwise.
        Since:
        6.0
      • checkedCast

        public static byte checkedCast(long value)
        Returns the byte value that, when treated as unsigned, is equal to value, if possible.
        Parameters:
        value - a value between 0 and 255 inclusive
        Returns:
        the byte value that, when treated as unsigned, equals value
        Throws:
        IllegalArgumentException - if value is negative or greater than 255
      • saturatedCast

        public static byte saturatedCast(long value)
        Returns the byte value that, when treated as unsigned, is nearest in value to value.
        Parameters:
        value - any long value
        Returns:
        (byte) 255 if value >= 255, (byte) 0 if value <= 0, and value cast to byte otherwise
      • compare

        public static int compare(byte a,
                                  byte b)
        Compares the two specified byte values, treating them as unsigned values between 0 and 255 inclusive. For example, (byte) -127 is considered greater than (byte) 127 because it is seen as having the value of positive 129.
        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
      • toString

        @Beta
        public static String toString(byte x)
        Returns a string representation of x, where x is treated as unsigned.
        Since:
        13.0
      • toString

        @Beta
        public static String toString(byte x,
                                            int radix)
        Returns a string representation of x for the given radix, where x is treated as unsigned.
        Parameters:
        x - the value to convert to a string.
        radix - the radix to use while working with x
        Throws:
        IllegalArgumentException - if radix is not between Character.MIN_RADIX and Character.MAX_RADIX.
        Since:
        13.0
      • parseUnsignedByte

        @Beta
        public static byte parseUnsignedByte(String string,
                                                   int radix)
        Returns the unsigned byte value represented by a string with the given radix.
        Parameters:
        string - the string containing the unsigned byte representation to be parsed.
        radix - the radix to use while parsing string
        Throws:
        NumberFormatException - if the string does not contain a valid unsigned byte with the given radix, or if radix is not between Character.MIN_RADIX and Character.MAX_RADIX.
        NullPointerException - if s is null (in contrast to Byte.parseByte(String))
        Since:
        13.0
      • join

        public static String join(String separator,
                                  byte... array)
        Returns a string containing the supplied byte values separated by separator. For example, join(":", (byte) 1, (byte) 2, (byte) 255) returns the string "1:2:255".
        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, 0x7F] < [0x01, 0x80] < [0x02]. Values are treated as unsigned.

        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:
        2.0
        See Also:
        Lexicographical order article at Wikipedia