io.greptime.limit

Class AbstractLimiter<In,Out>

java.lang.Object

io.greptime.limit.AbstractLimiter<In,Out>

Direct Known Subclasses:

WriteLimiter

public abstract class AbstractLimiter<In,Out>
extends Object

A Write/Query limiter that limits traffic according to the number of query requests or write request's data items in-flight.

If the number of permits requested at one time is greater than the total number of permits, we will allow this request under the condition that the available permits are equal to the maximum number of permits, i.e., there are no in-flight requests.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbstractLimiter.RejectedState

Constructor Summary

Constructors

Constructor and Description
AbstractLimiter(int maxInFlight, LimitedPolicy policy, String metricPrefix)

Method Summary

Modifier and Type	Method and Description
CompletableFuture<Out>	acquireAndDo(In in, java.util.function.Supplier<CompletableFuture<Out>> action) Acquire permits and do the action.
abstract int	calculatePermits(In in) Calculate the number of permits to acquire.
abstract Out	rejected(In in, AbstractLimiter.RejectedState state) The rejected action.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractLimiter

public AbstractLimiter(int maxInFlight,
                       LimitedPolicy policy,
                       String metricPrefix)

Method Detail

acquireAndDo

public CompletableFuture<Out> acquireAndDo(In in,
                                           java.util.function.Supplier<CompletableFuture<Out>> action)

Acquire permits and do the action.

Parameters:

in - input

action - the action to do

Returns:

the result of the action

calculatePermits

public abstract int calculatePermits(In in)

Calculate the number of permits to acquire.

Parameters:

in - input

Returns:

the number of permits to acquire

rejected

public abstract Out rejected(In in,
                             AbstractLimiter.RejectedState state)

The rejected action.

Parameters:

in - input

state - the rejected state

Returns:

the rejected result