com.netflix.concurrency.limits.limiter

Class BlockingLimiter<ContextT>

java.lang.Object

com.netflix.concurrency.limits.limiter.BlockingLimiter<ContextT>

Type Parameters:

ContextT -

All Implemented Interfaces:

Limiter<ContextT>

public final class BlockingLimiter<ContextT>
extends java.lang.Object
implements Limiter<ContextT>

Limiter that blocks the caller when the limit has been reached. The caller is blocked until the limiter has been released, or a timeout is reached. This limiter is commonly used in batch clients that use the limiter as a back-pressure mechanism.

Nested Class Summary

Nested classes/interfaces inherited from interface com.netflix.concurrency.limits.Limiter

Limiter.Listener

Field Summary

Fields

Modifier and Type	Field and Description
static java.time.Duration	MAX_TIMEOUT

Method Summary

Modifier and Type	Method and Description
java.util.Optional<Limiter.Listener>	acquire(ContextT context) Acquire a token from the limiter.
java.lang.String	toString()
static <ContextT> BlockingLimiter<ContextT>	wrap(Limiter<ContextT> delegate) Wrap a limiter such that acquire will block up to MAX_TIMEOUT if the limit was reached instead of return an empty listener immediately
static <ContextT> BlockingLimiter<ContextT>	wrap(Limiter<ContextT> delegate, java.time.Duration timeout) Wrap a limiter such that acquire will block up to a provided timeout if the limit was reached instead of return an empty listener immediately

Methods inherited from class java.lang.Object

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

Field Detail

MAX_TIMEOUT

public static final java.time.Duration MAX_TIMEOUT

Method Detail

wrap

public static <ContextT> BlockingLimiter<ContextT> wrap(Limiter<ContextT> delegate)

Wrap a limiter such that acquire will block up to MAX_TIMEOUT if the limit was reached instead of return an empty listener immediately

Parameters:

delegate - Non-blocking limiter to wrap

Returns:

Wrapped limiter

wrap

public static <ContextT> BlockingLimiter<ContextT> wrap(Limiter<ContextT> delegate,
                                                        java.time.Duration timeout)

Wrap a limiter such that acquire will block up to a provided timeout if the limit was reached instead of return an empty listener immediately

Parameters:

delegate - Non-blocking limiter to wrap

timeout - Max amount of time to wait for the wait for the limit to be released. Cannot exceed MAX_TIMEOUT

Returns:

Wrapped limiter

acquire

public java.util.Optional<Limiter.Listener> acquire(ContextT context)

Description copied from interface: Limiter

Acquire a token from the limiter. Returns an Optional.empty() if the limit has been exceeded. If acquired the caller must call one of the Listener methods when the operation has been completed to release the count.

Specified by:

acquire in interface Limiter<ContextT>

Parameters:

context - Context for the request

Returns:

Optional.empty() if limit exceeded.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object