Package convex.core.util

Class Bits

java.lang.Object
convex.core.util.Bits
public class Bits extends Object
Static utility function for bitwise functions

  • Constructor Summary

    Constructors
    Constructor
    Description
    Bits()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static int
    indexForDigit​(int digit, short mask)
    Returns the index from the present mask for the given hex digit (0-15), or -1 if not found
    static int
    leadingZeros​(int x)
    Get the number of leading zeros in the binary representation of an int
    static int
    leadingZeros​(long x)
    Get the number of leading zeros in the binary representation of a long
    static int
    lowBitMask​(int numBits)
    Gets a bit mask for the specified number of low bits in an int
    static int
    lowBits​(int numBits, int val)
    Gets the specified number of low Bits in an integer.
    static int
    positionForDigit​(int digit, short mask)
    Returns the array position for a given digit given a current mask.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Bits

      public Bits()

  • Method Details

    • indexForDigit

      public static int indexForDigit​(int digit, short mask)
      Returns the index from the present mask for the given hex digit (0-15), or -1 if not found
      Parameters:
      digit - Hex digit (0-15)
      mask - Bitmask of hex digits
      Returns:
      The index of the appropriate child for this digit, or -1 if not found

    • positionForDigit

      public static int positionForDigit​(int digit, short mask)
      Returns the array position for a given digit given a current mask. If not present, this is where the new array entry must be inserted.
      Parameters:
      digit - Hex digit (0-15)
      mask - Bitmask of hex digits
      Returns:
      Array position for the given digit in the specified mask

    • leadingZeros

      public static int leadingZeros​(int x)
      Get the number of leading zeros in the binary representation of an int
      Parameters:
      x - int value to check
      Returns:
      Number of leading zeros (0-32)

    • leadingZeros

      public static int leadingZeros​(long x)
      Get the number of leading zeros in the binary representation of a long
      Parameters:
      x - long value to check
      Returns:
      Number of leading zeros (0-64)

    • lowBitMask

      public static int lowBitMask​(int numBits)
      Gets a bit mask for the specified number of low bits in an int
      Parameters:
      numBits - Number of bits to set to 1
      Returns:
      int containing the specified number of set low bits

    • lowBits

      public static int lowBits​(int numBits, int val)
      Gets the specified number of low Bits in an integer. Other bits are zeroed.
      Parameters:
      numBits - Number of bits to get
      val - Value to extract bits from
      Returns:
      Masked in with the specified number of low bits