Package one.microstream.math

Class Countdown

java.lang.Object
one.microstream.math.Countdown
public class Countdown
extends Object
Class that wraps a combination of start value and remaining value to implement a countdown.
The countdown can be decremented, resetted and be checked for having expired or still being active.

  • Constructor Summary

    Constructors 
    Constructor Description
    Countdown​(int startValue)
    Instantiates a new countdown with a given start value.

  • Method Summary

    Modifier and Type Method Description
    int decrease​(int offset)  
    int decrement()
    Decrements this countdown by 1.
    int expire()
    Immediately expires this countdown.
    int getRemainingValue()  
    int getStartValue()  
    boolean isActive()
    Tells if this countdown is still active (meaning its remaining value is greater than 0)
    boolean isAtStart()
    Tells if this countdown is still full (meaning its remaining value is equal to its start value)
    boolean isExpired()
    Tells if this countdown is expired(meaning its remaining value is 0)
    int reset()
    Resets this countdown to its start value.
    String toString()  

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Countdown

      public Countdown​(int startValue)
      Instantiates a new countdown with a given start value.
      Parameters:
      startValue - may not be negative

  • Method Details

    • getStartValue

      public int getStartValue()
      Returns:
      the start value of this countdown. Cannot be negative.

    • getRemainingValue

      public int getRemainingValue()
      Returns:
      the remaining value of this countdown. Will always be in the range [0;startValue]

    • toString

      public String toString()
      Overrides:
      toString in class Object
      Returns:
      a String representing the plain remaining value of this countdown.

    • decrement

      public int decrement()
      Decrements this countdown by 1.
      Returns:
      1 if the countdown already expired, 0 otherwise (returns the unconsumed amount of value 1)
      See Also:
      decrease(int)

    • decrease

      public int decrease​(int offset)
      Parameters:
      offset - the offset to decrease this countdown with
      Returns:
      the unconsumed amount of offset due to preterm expiration of the countdown.
      See Also:
      decrement()

    • reset

      public int reset()
      Resets this countdown to its start value.
      Returns:
      the remaining countdown value before the reset.

    • expire

      public int expire()
      Immediately expires this countdown.
      Returns:
      the remaining countdown value before the expiration.

    • isActive

      public boolean isActive()
      Tells if this countdown is still active (meaning its remaining value is greater than 0)
      Returns:
      true if this countdown's remaining value is greater 0, false otherwise.
      See Also:
      isAtStart(), isExpired()

    • isExpired

      public boolean isExpired()
      Tells if this countdown is expired(meaning its remaining value is 0)
      Returns:
      true if this countdown's remaining value 0, false otherwise.
      See Also:
      isActive(), isAtStart()

    • isAtStart

      public boolean isAtStart()
      Tells if this countdown is still full (meaning its remaining value is equal to its start value)
      Returns:
      true if this countdown's remaining value is the same as its start value, false otherwise.
      See Also:
      isActive(), isExpired()