com.hazelcast.util

## Class QuickMath

- java.lang.Object
- - com.hazelcast.util.QuickMath

-     public final class QuickMath
      extends Object

  The class `QuickMath` contains methods to perform optimized mathematical operations. Methods are allowed to put additional constraints on the range of input values if required for efficiency. Methods are not required to perform validation of input arguments, but they have to indicate the constraints in theirs contract.

- - ### Method Summary

    All Methods Static Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `static String` | `bytesToHex(byte[] in)`
    `static int` | `compareIntegers(int i1, int i2)` Compares two integers
    `static int` | `compareLongs(long l1, long l2)` Compares two longs
    `static int` | `divideByAndCeilToInt(double d, int k)` Divide d by k and return the smallest integer greater than or equal to the result.
    `static long` | `divideByAndCeilToLong(double d, int k)` Divide d by k and return the smallest integer greater than or equal to the result.
    `static int` | `divideByAndRoundToInt(double d, int k)` Divide d by k and return the int value closest to the result.
    `static long` | `divideByAndRoundToLong(double d, int k)` Divide d by k and return the long value closest to the result.
    `static boolean` | `isPowerOfTwo(long x)` Return true if input argument is power of two.
    `static int` | `log2(int value)` Return the log 2 result for this int.
    `static int` | `log2(long value)` Return the log 2 result for this long.
    `static int` | `modPowerOfTwo(int a, int b)` Computes the remainder of the division of `a` by `b`.
    `static long` | `modPowerOfTwo(long a, int b)` Computes the remainder of the division of `a` by `b`.
    `static int` | `nextPowerOfTwo(int value)` Fast method of finding the next power of 2 greater than or equal to the supplied value.
    `static long` | `nextPowerOfTwo(long value)` Fast method of finding the next power of 2 greater than or equal to the supplied value.
    `static int` | `normalize(int value, int factor)` Divide value by factor, take the smallest integer greater than or equal to the result, multiply that integer by factor, and return it.
    `static long` | `normalize(long value, int factor)` Divide value by factor, take the smallest integer greater than or equal to the result, multiply that integer by factor, and return it.

    - ### Methods inherited from class java.lang.Object

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

- - ### Method Detail

    - #### isPowerOfTwo

          public static boolean isPowerOfTwo(long x)

      Return true if input argument is power of two. Input has to be a a positive integer.

      Result is undefined for zero or negative integers.
      Parameters:
        `x` - test `x` to see if it is a power of two
      Returns:
        `true` if `x` is power of two

    - #### modPowerOfTwo

          public static int modPowerOfTwo(int a,
                                          int b)

      Computes the remainder of the division of `a` by `b`. `a` has to be a non-negative integer and `b` has to be a power of two, otherwise the result is undefined.
      Parameters:
        `a` - divide a by b. a must be a non-negative integer
        `b` - divide a by b. b must be a power of two
      Returns:
        remainder of the division of a by b.

    - #### modPowerOfTwo

          public static long modPowerOfTwo(long a,
                                           int b)

      Computes the remainder of the division of `a` by `b`. `a` has to be a non-negative integer and `b` has to be a power of two, otherwise the result is undefined.
      Parameters:
        `a` - divide a by b. a must be a non-negative integer
        `b` - divide a by b. b must be a power of two
      Returns:
        remainder of the division of a by b.

    - #### nextPowerOfTwo

          public static int nextPowerOfTwo(int value)

      Fast method of finding the next power of 2 greater than or equal to the supplied value.

      If the value is <= 0 then 1 will be returned.

      This method is not suitable for `Integer.MIN_VALUE` or numbers greater than 2^30.
      Parameters:
        `value` - from which to search for next power of 2
      Returns:
        The next power of 2 or the value itself if it is a power of 2

    - #### nextPowerOfTwo

          public static long nextPowerOfTwo(long value)

      Fast method of finding the next power of 2 greater than or equal to the supplied value.

      If the value is <= 0 then 1 will be returned.

      This method is not suitable for `Long.MIN_VALUE` or numbers greater than 2^62.
      Parameters:
        `value` - from which to search for next power of 2
      Returns:
        The next power of 2 or the value itself if it is a power of 2

    - #### log2

          public static int log2(int value)

      Return the log 2 result for this int.
      Parameters:
        `value` - the int value
      Returns:
        the log 2 result for value

    - #### log2

          public static int log2(long value)

      Return the log 2 result for this long.
      Parameters:
        `value` - the long value
      Returns:
        the log 2 result for value

    - #### divideByAndCeilToInt

          public static int divideByAndCeilToInt(double d,
                                                 int k)

      Divide d by k and return the smallest integer greater than or equal to the result.
      Parameters:
        `d` - divide d by k
        `k` - divide d by k
      Returns:
        the smallest integer greater than or equal to the result

    - #### divideByAndCeilToLong

          public static long divideByAndCeilToLong(double d,
                                                   int k)

      Divide d by k and return the smallest integer greater than or equal to the result.
      Parameters:
        `d` - divide d by k
        `k` - divide d by k
      Returns:
        the smallest integer greater than or equal to the result

    - #### divideByAndRoundToInt

          public static int divideByAndRoundToInt(double d,
                                                  int k)

      Divide d by k and return the int value closest to the result.
      Parameters:
        `d` - divide d by k
        `k` - divide d by k
      Returns:
        the int value closest to the result

    - #### divideByAndRoundToLong

          public static long divideByAndRoundToLong(double d,
                                                    int k)

      Divide d by k and return the long value closest to the result.
      Parameters:
        `d` - divide d by k
        `k` - divide d by k
      Returns:
        the long value closest to the result

    - #### normalize

          public static int normalize(int value,
                                      int factor)

      Divide value by factor, take the smallest integer greater than or equal to the result, multiply that integer by factor, and return it.
      Parameters:
        `value` - normalize this value by factor
        `factor` - normalize this value by factor
      Returns:
        the result of value being normalized by factor

    - #### normalize

          public static long normalize(long value,
                                       int factor)

      Divide value by factor, take the smallest integer greater than or equal to the result, multiply that integer by factor, and return it.
      Parameters:
        `value` - normalize this value by factor
        `factor` - normalize this value by factor
      Returns:
        the result of value being normalized by factor

    - #### bytesToHex

          public static String bytesToHex(byte[] in)

    - #### compareIntegers

          public static int compareIntegers(int i1,
                                            int i2)

      Compares two integers
      Parameters:
        `i1` - First number to compare with second one
        `i2` - Second number to compare with first one
      Returns:
        +1 if i1 > i2, -1 if i2 > i1, 0 if i1 and i2 are equals

    - #### compareLongs

          public static int compareLongs(long l1,
                                         long l2)

      Compares two longs
      Parameters:
        `l1` - First number to compare with second one
        `l2` - Second number to compare with first one
      Returns:
        +1 if l1 > l2, -1 if l2 > l1, 0 if l1 and l2 are equals

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