org.dromara.hutool.core.thread.ratelimiter

Class SemaphoreRateLimiter

java.lang.Object

org.dromara.hutool.core.thread.ratelimiter.SemaphoreRateLimiter

All Implemented Interfaces:

RateLimiter

Direct Known Subclasses:

TokenBucketRateLimiter

public abstract class SemaphoreRateLimiter
extends Object
implements RateLimiter

基于Semaphore 实现的限流器

Since:

6.0.0

Author:

Ricky Fung, Looly

Field Summary

Fields

Modifier and Type	Field and Description
protected RateLimiterConfig	config
protected Semaphore	semaphore

Constructor Summary

Constructors

Constructor and Description
SemaphoreRateLimiter(RateLimiterConfig config) 构造
SemaphoreRateLimiter(RateLimiterConfig config, Semaphore semaphore) 构造

Method Summary

Modifier and Type	Method and Description
void	acquire(int permits) 获取许可，阻塞方法，如果没有足够的许可，则阻塞等待
abstract void	refreshLimit() 刷新限制，用户可重写此方法，改变填充许可方式，如： 填满窗口，一般用于固定窗口（Fixed Window） 固定频率填充，如每个周期只填充1个，配合RateLimiterConfig.getRefreshPeriod()，可实现令牌桶（Token Bucket） 同样，用户可通过调用此方法手动刷新 注意：重写此方法前需判断许可是否已满
boolean	tryAcquire(int permits) 尝试获取许可，非阻塞方法

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.dromara.hutool.core.thread.ratelimiter.RateLimiter

acquire, tryAcquire

Field Detail

config

protected final RateLimiterConfig config

semaphore

protected final Semaphore semaphore

Constructor Detail

SemaphoreRateLimiter

public SemaphoreRateLimiter(RateLimiterConfig config)

构造

Parameters:

config - 限流配置

SemaphoreRateLimiter

public SemaphoreRateLimiter(RateLimiterConfig config,
                            Semaphore semaphore)

构造

Parameters:

config - 限流配置

semaphore - Semaphore，默认使用RateLimiterConfig.getCapacity()创建

Method Detail

tryAcquire

public boolean tryAcquire(int permits)

Description copied from interface: RateLimiter

尝试获取许可，非阻塞方法

Specified by:

tryAcquire in interface RateLimiter

Parameters:

permits - 需要的许可数

Returns:

true表示成功获取，false表示无足够的许可可获取，此时需要等待给定的时间

acquire

public void acquire(int permits)

Description copied from interface: RateLimiter

获取许可，阻塞方法，如果没有足够的许可，则阻塞等待

Specified by:

acquire in interface RateLimiter

Parameters:

permits - 需要的许可数

refreshLimit

public abstract void refreshLimit()

刷新限制，用户可重写此方法，改变填充许可方式，如：

• 填满窗口，一般用于固定窗口（Fixed Window）
• 固定频率填充，如每个周期只填充1个，配合RateLimiterConfig.getRefreshPeriod()，可实现令牌桶（Token Bucket）

同样，用户可通过调用此方法手动刷新
注意：重写此方法前需判断许可是否已满

See Also:

RateLimiterConfig.getCapacity()