Package org.apache.logging.log4j.core.util

Class Integers

  • public final class Integers
extends java.lang.Object
    Helps deal with integers.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private static int BITS_PER_INT  

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      private Integers()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static int ceilingNextPowerOfTwo​(int x)
      Calculate the next power of 2, greater than or equal to x.
      static int parseInt​(java.lang.String s)
      Parses the string argument as a signed decimal integer.
      static int parseInt​(java.lang.String s, int defaultValue)
      Parses the string argument as a signed decimal integer.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • Integers

        private Integers()

    • Method Detail

      • parseInt

        public static int parseInt​(java.lang.String s,
                           int defaultValue)
        Parses the string argument as a signed decimal integer.

        The input may be surrounded by whitespace.

        Parameters:
        s - a String containing the int representation to parse, may be null or ""
        defaultValue - the return value, use defaultValue if s is null or ""
        Returns:
        the integer value represented by the argument in decimal.
        Throws:
        java.lang.NumberFormatException - if the string does not contain a parsable integer.

      • parseInt

        public static int parseInt​(java.lang.String s)
        Parses the string argument as a signed decimal integer.
        Parameters:
        s - a String containing the int representation to parse, may be null or ""
        Returns:
        the integer value represented by the argument in decimal.
        Throws:
        java.lang.NumberFormatException - if the string does not contain a parsable integer.

      • ceilingNextPowerOfTwo

        public static int ceilingNextPowerOfTwo​(int x)
        Calculate the next power of 2, greater than or equal to x.

        From Hacker's Delight, Chapter 3, Harry S. Warren Jr.

        Parameters:
        x - Value to round up
        Returns:
        The next power of 2 from x inclusive