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 and Description
Countdown(int startValue) Instantiates a new countdown with a given start value.

Method Summary

Modifier and Type	Method and 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 Detail

Countdown

public Countdown(int startValue)

Instantiates a new countdown with a given start value.

Parameters:

startValue - may not be negative

Method Detail

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()