Class UnsignedLongs

java.lang.Object
com.google.common.primitives.UnsignedLongs
@GwtCompatible public final class UnsignedLongs extends Object
Static utility methods pertaining to long primitives that interpret values as unsigned (that is, any negative value x is treated as the positive value 2^64 + x). The methods for which signedness is not an issue are in Longs, as well as signed versions of methods for which signedness is an issue.

In addition, this class provides several static methods for converting a long to a String and a String to a long that treat the long as an unsigned number.

Users of these utilities must be extremely careful not to mix up signed and unsigned long values. When possible, it is recommended that the UnsignedLong wrapper class be used, at a small efficiency penalty, to enforce the distinction in the type system.

See the Guava User Guide article on unsigned primitive utilities.

Since:
10.0
Author:
Louis Wasserman, Brian Milch, Colin Evans

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final long
    MAX_VALUE
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static int
    compare(long a, long b)
    Compares the two specified long values, treating them as unsigned values between 0 and 2^64 - 1 inclusive.
    static long
    decode(String stringValue)
    Returns the unsigned long value represented by the given string.
    static long
    divide(long dividend, long divisor)
    Returns dividend / divisor, where the dividend and divisor are treated as unsigned 64-bit quantities.
    static String
    join(String separator, long... array)
    Returns a string containing the supplied unsigned long values separated by separator.
    static Comparator<long[]>
    lexicographicalComparator()
    Returns a comparator that compares two arrays of unsigned long values lexicographically.
    static long
    max(long... array)
    Returns the greatest value present in array, treating values as unsigned.
    static long
    min(long... array)
    Returns the least value present in array, treating values as unsigned.
    static long
    parseUnsignedLong(String string)
    Returns the unsigned long value represented by the given decimal string.
    static long
    parseUnsignedLong(String string, int radix)
    Returns the unsigned long value represented by a string with the given radix.
    static long
    remainder(long dividend, long divisor)
    Returns dividend % divisor, where the dividend and divisor are treated as unsigned 64-bit quantities.
    static void
    sort(long[] array)
    Sorts the array, treating its elements as unsigned 64-bit integers.
    static void
    sort(long[] array, int fromIndex, int toIndex)
    Sorts the array between fromIndex inclusive and toIndex exclusive, treating its elements as unsigned 64-bit integers.
    static void
    sortDescending(long[] array)
    Sorts the elements of array in descending order, interpreting them as unsigned 64-bit integers.
    static void
    sortDescending(long[] array, int fromIndex, int toIndex)
    Sorts the elements of array between fromIndex inclusive and toIndex exclusive in descending order, interpreting them as unsigned 64-bit integers.
    static String
    toString(long x)
    Returns a string representation of x, where x is treated as unsigned.
    static String
    toString(long x, int radix)
    Returns a string representation of x for the given radix, where x is treated as unsigned.

    Methods inherited from class java.lang.Object

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

  • Field Details

  • Method Details

    • compare

      public static int compare(long a, long b)
      Compares the two specified long values, treating them as unsigned values between 0 and 2^64 - 1 inclusive.

      Note: this method is now unnecessary and should be treated as deprecated; use the equivalent Long.compareUnsigned(long, long) method instead.

      Parameters:
      a - the first unsigned long to compare
      b - the second unsigned long 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 long min(long... array)
      Returns the least value present in array, treating values as unsigned.
      Parameters:
      array - a nonempty array of unsigned long values
      Returns:
      the value present in array that is less than or equal to every other value in the array according to compare(long, long)
      Throws:
      IllegalArgumentException - if array is empty

    • max

      public static long max(long... array)
      Returns the greatest value present in array, treating values as unsigned.
      Parameters:
      array - a nonempty array of unsigned long values
      Returns:
      the value present in array that is greater than or equal to every other value in the array according to compare(long, long)
      Throws:
      IllegalArgumentException - if array is empty

    • join

      public static String join(String separator, long... array)
      Returns a string containing the supplied unsigned long values separated by separator. For example, join("-", 1, 2, 3) returns the string "1-2-3".
      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 unsigned long values, possibly empty

    • lexicographicalComparator

      public static Comparator<long[]> lexicographicalComparator()
      Returns a comparator that compares two arrays of unsigned long values lexicographically. That is, it compares, using compare(long, long)), 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, [] < [1L] < [1L, 2L] < [2L] < [1L << 63].

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

      Java 9+ users: Use Arrays::compareUnsigned.

    • sort

      public static void sort(long[] array)
      Sorts the array, treating its elements as unsigned 64-bit integers.
      Since:
      23.1

    • sort

      public static void sort(long[] array, int fromIndex, int toIndex)
      Sorts the array between fromIndex inclusive and toIndex exclusive, treating its elements as unsigned 64-bit integers.
      Since:
      23.1

    • sortDescending

      public static void sortDescending(long[] array)
      Sorts the elements of array in descending order, interpreting them as unsigned 64-bit integers.
      Since:
      23.1

    • sortDescending

      public static void sortDescending(long[] array, int fromIndex, int toIndex)
      Sorts the elements of array between fromIndex inclusive and toIndex exclusive in descending order, interpreting them as unsigned 64-bit integers.
      Since:
      23.1

    • divide

      public static long divide(long dividend, long divisor)
      Returns dividend / divisor, where the dividend and divisor are treated as unsigned 64-bit quantities.

      Java 8+ users: use Long.divideUnsigned(long, long) instead.

      Parameters:
      dividend - the dividend (numerator)
      divisor - the divisor (denominator)
      Throws:
      ArithmeticException - if divisor is 0

    • remainder

      public static long remainder(long dividend, long divisor)
      Returns dividend % divisor, where the dividend and divisor are treated as unsigned 64-bit quantities.

      Java 8+ users: use Long.remainderUnsigned(long, long) instead.

      Parameters:
      dividend - the dividend (numerator)
      divisor - the divisor (denominator)
      Throws:
      ArithmeticException - if divisor is 0
      Since:
      11.0

    • parseUnsignedLong

      @CanIgnoreReturnValue public static long parseUnsignedLong(String string)
      Returns the unsigned long value represented by the given decimal string.

      Java 8+ users: use Long.parseUnsignedLong(String) instead.

      Throws:
      NumberFormatException - if the string does not contain a valid unsigned long value
      NullPointerException - if string is null (in contrast to Long.parseLong(String))

    • parseUnsignedLong

      @CanIgnoreReturnValue public static long parseUnsignedLong(String string, int radix)
      Returns the unsigned long value represented by a string with the given radix.

      Java 8+ users: use Long.parseUnsignedLong(String, int) instead.

      Parameters:
      string - the string containing the unsigned long representation to be parsed.
      radix - the radix to use while parsing string
      Throws:
      NumberFormatException - if the string does not contain a valid unsigned long with the given radix, or if radix is not between Character.MIN_RADIX and Character.MAX_RADIX.
      NullPointerException - if string is null (in contrast to Long.parseLong(String))

    • decode

      @CanIgnoreReturnValue public static long decode(String stringValue)
      Returns the unsigned long value represented by the given string.

      Accepts a decimal, hexadecimal, or octal number given by specifying the following prefix:

      • 0xHexDigits
      • 0XHexDigits
      • #HexDigits
      • 0OctalDigits
      Throws:
      NumberFormatException - if the string does not contain a valid unsigned long value
      Since:
      13.0

    • toString

      public static String toString(long x)
      Returns a string representation of x, where x is treated as unsigned.

      Java 8+ users: use Long.toUnsignedString(long) instead.

    • toString

      public static String toString(long x, int radix)
      Returns a string representation of x for the given radix, where x is treated as unsigned.

      Java 8+ users: use Long.toUnsignedString(long, int) instead.

      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.