com.linecorp.armeria.common.stream

Class AbstractStreamMessageDuplicator<T,U extends StreamMessage<T>>

java.lang.Object

com.linecorp.armeria.common.stream.AbstractStreamMessageDuplicator<T,U>

Type Parameters:

T - the type of elements

U - the type of the upstream StreamMessage and duplicated StreamMessages

All Implemented Interfaces:

SafeCloseable, AutoCloseable

Direct Known Subclasses:

HttpRequestDuplicator, HttpResponseDuplicator

public abstract class AbstractStreamMessageDuplicator<T,U extends StreamMessage<T>>
extends Object
implements SafeCloseable

Allows subscribing to a StreamMessage multiple times by duplicating the stream.

Only one subscriber can subscribe other stream messages such as DefaultStreamMessage, DeferredStreamMessage, etc. This factory is wrapping one of those StreamMessages and spawns duplicated stream messages which are created using duplicateStream() and subscribed by subscribers one by one.

The published elements can be shared across Subscribers, if you subscribe with the SubscriptionOption.WITH_POOLED_OBJECTS, so do not manipulate the data unless you copy them.

This factory has to be closed by close() when you do not need the contents anymore, otherwise memory leak might happen.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractStreamMessageDuplicator(U upstream, SignalLengthGetter<? super T> signalLengthGetter, io.netty.util.concurrent.EventExecutor executor, long maxSignalLength) Creates a new instance which subscribes to the specified upstream StreamMessage and publishes to multiple subscribers.

Method Summary

Modifier and Type	Method and Description
void	abort() Closes this duplicator and aborts all stream messages returned by duplicateStream().
void	abort(Throwable cause) Closes this duplicator and aborts all stream messages returned by duplicateStream() with the specified Throwable.
void	close() Closes this duplicator and prevents it from further duplication.
StreamMessage<T>	duplicateStream() Creates a new StreamMessage that duplicates the upstream StreamMessage specified when creating this duplicator.
StreamMessage<T>	duplicateStream(boolean lastStream) Creates a new StreamMessage that duplicates the upstream StreamMessage specified when creating this duplicator.
protected io.netty.util.concurrent.EventExecutor	duplicatorExecutor() Returns the default EventExecutor which will be used when a user subscribes to a child stream using StreamMessage.subscribe(Subscriber, SubscriptionOption...).

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractStreamMessageDuplicator

protected AbstractStreamMessageDuplicator(U upstream,
                                          SignalLengthGetter<? super T> signalLengthGetter,
                                          @Nullable
                                          io.netty.util.concurrent.EventExecutor executor,
                                          long maxSignalLength)

Creates a new instance which subscribes to the specified upstream StreamMessage and publishes to multiple subscribers.

Parameters:

upstream - the StreamMessage who will publish data to subscribers

signalLengthGetter - the signal length getter that produces the length of signals

executor - the executor to use for upstream signals

maxSignalLength - the maximum length of signals. 0 disables the length limit

Method Detail

duplicateStream

public StreamMessage<T> duplicateStream()

Creates a new StreamMessage that duplicates the upstream StreamMessage specified when creating this duplicator.

duplicateStream

public StreamMessage<T> duplicateStream(boolean lastStream)

Creates a new StreamMessage that duplicates the upstream StreamMessage specified when creating this duplicator.

Parameters:

lastStream - whether to prevent further duplication

duplicatorExecutor

protected io.netty.util.concurrent.EventExecutor duplicatorExecutor()

Returns the default EventExecutor which will be used when a user subscribes to a child stream using StreamMessage.subscribe(Subscriber, SubscriptionOption...).

close

public void close()

Closes this duplicator and prevents it from further duplication. duplicateStream() will raise an IllegalStateException after this method is invoked. Note that the previously duplicated streams will not be closed but will continue publishing data until the upstream StreamMessage is closed. All the data published from the upstream StreamMessage are cleaned up when all duplicated streams are complete.

Specified by:

close in interface SafeCloseable

Specified by:

close in interface AutoCloseable

abort

public void abort()

Closes this duplicator and aborts all stream messages returned by duplicateStream(). This will also clean up the data published from the upstream StreamMessage.

abort

public void abort(Throwable cause)

Closes this duplicator and aborts all stream messages returned by duplicateStream() with the specified Throwable. This will also clean up the data published from the upstream StreamMessage.