Package com.linecorp.armeria.client.limit

Class ConcurrencyLimitingClient<I extends Request,O extends Response>

java.lang.Object

com.linecorp.armeria.client.DecoratingClient<I,O,I,O>

com.linecorp.armeria.client.SimpleDecoratingClient<I,O>

com.linecorp.armeria.client.limit.ConcurrencyLimitingClient<I,O>

Type Parameters:

I - the Request type

O - the Response type

All Implemented Interfaces:

Client<I,O>

Direct Known Subclasses:

ConcurrencyLimitingHttpClient

public abstract class ConcurrencyLimitingClient<I extends Request,O extends Response>
extends SimpleDecoratingClient<I,O>

An abstract Client decorator that limits the concurrent number of active requests.

numActiveRequests() increases when Client.execute(ClientRequestContext, Request) is invoked and decreases when the Response returned by the Client.execute(ClientRequestContext, Request) is closed. When numActiveRequests() reaches at the configured maxConcurrency the Requests are deferred until the currently active Requests are completed.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ConcurrencyLimitingClient.Deferred<O extends Response>	Provides the interface for updating the result of a Request execution when its Response is ready.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ConcurrencyLimitingClient(Client<I,O> delegate, int maxConcurrency)	Creates a new instance that decorates the specified delegate to limit the concurrent number of active requests to maxConcurrency, with the default timeout of 10000L milliseconds.
protected	ConcurrencyLimitingClient(Client<I,O> delegate, int maxConcurrency, long timeout, TimeUnit unit)	Creates a new instance that decorates the specified delegate to limit the concurrent number of active requests to maxConcurrency.

Method Summary

Modifier and Type	Method	Description
protected abstract ConcurrencyLimitingClient.Deferred<O>	defer(ClientRequestContext ctx, I req)	Defers the specified Request.
O	execute(ClientRequestContext ctx, I req)	Sends a Request to a remote Endpoint, as specified in ClientRequestContext.endpoint().
int	numActiveRequests()	Returns the number of the Requests that are being executed.

Methods inherited from class com.linecorp.armeria.client.DecoratingClient

delegate, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ConcurrencyLimitingClient

protected ConcurrencyLimitingClient(Client<I,O> delegate,
                                    int maxConcurrency)

Creates a new instance that decorates the specified delegate to limit the concurrent number of active requests to maxConcurrency, with the default timeout of 10000L milliseconds.

Parameters:

delegate - the delegate Client

maxConcurrency - the maximum number of concurrent active requests. 0 to disable the limit.

ConcurrencyLimitingClient

protected ConcurrencyLimitingClient(Client<I,O> delegate,
                                    int maxConcurrency,
                                    long timeout,
                                    TimeUnit unit)

Creates a new instance that decorates the specified delegate to limit the concurrent number of active requests to maxConcurrency.

Parameters:

delegate - the delegate Client

maxConcurrency - the maximum number of concurrent active requests. 0 to disable the limit.

timeout - the amount of time until this decorator fails the request if the request was not delegated to the delegate before then

Method Detail

numActiveRequests

public int numActiveRequests()

Returns the number of the Requests that are being executed.

execute

public O execute(ClientRequestContext ctx,
                 I req)
          throws Exception

Description copied from interface: Client

Sends a Request to a remote Endpoint, as specified in ClientRequestContext.endpoint().

Returns:

the Response to the specified Request

Throws:

Exception

defer

protected abstract ConcurrencyLimitingClient.Deferred<O> defer(ClientRequestContext ctx,
                                                               I req)
                                                        throws Exception

Defers the specified Request.

Returns:

a new ConcurrencyLimitingClient.Deferred which provides the interface for updating the result of Request execution later.

Throws:

Exception