io.github.bucket4j

Enum TokensInheritanceStrategy

java.lang.Object

java.lang.Enum<TokensInheritanceStrategy>

io.github.bucket4j.TokensInheritanceStrategy

All Implemented Interfaces:

Serializable, Comparable<TokensInheritanceStrategy>

public enum TokensInheritanceStrategy
extends Enum<TokensInheritanceStrategy>

Specifies the rules for inheritance of available tokens when Bucket.replaceConfiguration(BucketConfiguration, TokensInheritanceStrategy) happens.

Enum Constant Summary

Enum Constants

Enum Constant and Description
ADDITIVE Instructs to copy available tokens as is, but with one exclusion: if new bandwidth capacity is greater than old capacity, available tokens will be increased by the difference between the old and the new configuration.
AS_IS Instructs to copy available tokens as is, but with one exclusion: if available tokens is greater than new capacity, available tokens will be decreased to new capacity.
PROPORTIONALLY Makes to copy available tokens proportional to bandwidth capacity by following formula: newAvailableTokens = availableTokensBeforeReplacement * (newBandwidthCapacity / capacityBeforeReplacement)
RESET Use this mode when you want just to forget about previous bucket state.

Method Summary

Modifier and Type	Method and Description
static TokensInheritanceStrategy	getById(byte id)
byte	getId()
static TokensInheritanceStrategy	valueOf(String name) Returns the enum constant of this type with the specified name.
static TokensInheritanceStrategy[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

PROPORTIONALLY

public static final TokensInheritanceStrategy PROPORTIONALLY

Makes to copy available tokens proportional to bandwidth capacity by following formula: newAvailableTokens = availableTokensBeforeReplacement * (newBandwidthCapacity / capacityBeforeReplacement)

Let's describe few examples.

Example 1: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(200, Refill.gready(10, Duration.ofMinutes(1))) 40 available tokens will be multiplied by 2(200/100), and after replacement we will have 80 available tokens.

Example 2: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(20, Refill.gready(10, Duration.ofMinutes(1))) 40 available tokens will be multiplied by 0.2(20/100), and after replacement we will have 8 available tokens.

AS_IS

public static final TokensInheritanceStrategy AS_IS

Instructs to copy available tokens as is, but with one exclusion: if available tokens is greater than new capacity, available tokens will be decreased to new capacity.

Let's describe few examples.

Example 1: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(200, Refill.gready(10, Duration.ofMinutes(1))) 40 available tokens will be just copied, and after replacement we will have 40 available tokens.

Example 2: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(20, Refill.gready(10, Duration.ofMinutes(1))) 40 available tokens can not be copied as is, because it is greater then new capacity, so available tokens will be reduced to 20.

RESET

public static final TokensInheritanceStrategy RESET

Use this mode when you want just to forget about previous bucket state. bucket.replaceConfiguration(newConfiguration, TokensInheritanceStrategy.RESET) just erases all previous state. Using this strategy equals to removing bucket and creating again with new configuration.

ADDITIVE

public static final TokensInheritanceStrategy ADDITIVE

Instructs to copy available tokens as is, but with one exclusion: if new bandwidth capacity is greater than old capacity, available tokens will be increased by the difference between the old and the new configuration.

The formula is newAvailableTokens = Math.min(availableTokensBeforeReplacement, newBandwidthCapacity) + Math.max(0, newBandwidthCapacity - capacityBeforeReplacement)

Let's describe few examples.

Example 1: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of configuration replacement, it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(200, Refill.gready(10, Duration.ofMinutes(1))) 40 available tokens will be copied and added to the difference between old and new configuration, and after replacement, we will have 140 available tokens.

Example 2: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 40 available tokens. After replacing this bandwidth by following Bandwidth.classic(20, Refill.gready(10, Duration.ofMinutes(1)))), and after replacement we will have 20 available tokens.

Example 3: imagine bandwidth that was created by Bandwidth.classic(100, Refill.gready(10, Duration.ofMinutes(1))). At the moment of config replacement it was 10 available tokens. After replacing this bandwidth by following Bandwidth.classic(20, Refill.gready(10, Duration.ofMinutes(1)))), and after replacement we will have 10 available tokens.

Method Detail

values

public static TokensInheritanceStrategy[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (TokensInheritanceStrategy c : TokensInheritanceStrategy.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static TokensInheritanceStrategy valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

getById

public static TokensInheritanceStrategy getById(byte id)

getId

public byte getId()