Package com.linecorp.armeria.common.stream

Interface StreamWriter<T>

Type Parameters:

T - the type of the stream element

All Known Subinterfaces:

HttpRequestWriter, HttpResponseWriter

All Known Implementing Classes:

DefaultStreamMessage

public interface StreamWriter<T>

Produces the objects to be published by a StreamMessage.

Life cycle of reference-counted objects

When the following methods are given with a pooled HttpData or the Supplier that provides such an object:

• tryWrite(Object)
• tryWrite(Supplier)
• write(Object)
• write(Supplier)
• close(Throwable)

the object will be released automatically by the stream when it's no longer in use, such as when:

• The method returns false or raises an exception.
• The Subscriber of the stream consumes it.
• The stream is cancelled, aborted or failed.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes the StreamMessage successfully.
void	close(Throwable cause)	Closes the StreamMessage exceptionally.
boolean	isOpen()	Returns true if the StreamMessage is open.
default boolean	tryWrite(Supplier<? extends T> o)	Writes the specified object Supplier to the StreamMessage.
boolean	tryWrite(T o)	Writes the specified object to the StreamMessage.
CompletableFuture<Void>	whenConsumed()	Returns a CompletableFuture which is completed when all elements written so far have been consumed by the Subscriber.
default void	write(Supplier<? extends T> o)	Writes the specified object Supplier to the StreamMessage.
default void	write(T o)	Writes the specified object to the StreamMessage.

Method Details

isOpen

boolean isOpen()

Returns true if the StreamMessage is open.

write

default void write(T o)

Writes the specified object to the StreamMessage. The written object will be transferred to the Subscriber.

Throws:

ClosedStreamException - if the stream was already closed

IllegalArgumentException - if the publication of the specified object has been rejected

See Also:

Life cycle of reference-counted objects

write

default void write(Supplier<? extends T> o)

Writes the specified object Supplier to the StreamMessage. The object provided by the Supplier will be transferred to the Subscriber.

Throws:

ClosedStreamException - if the stream was already closed.

See Also:

Life cycle of reference-counted objects

tryWrite

@CheckReturnValue
boolean tryWrite(T o)

Writes the specified object to the StreamMessage. The written object will be transferred to the Subscriber.

Returns:

true if the specified object has been scheduled for publication. false if the stream has been closed already.

Throws:

IllegalArgumentException - if the publication of the specified object has been rejected

See Also:

Life cycle of reference-counted objects

tryWrite

@CheckReturnValue
default boolean tryWrite(Supplier<? extends T> o)

Writes the specified object Supplier to the StreamMessage. The object provided by the Supplier will be transferred to the Subscriber.

Returns:

true if the specified object has been scheduled for publication. false if the stream has been closed already.

See Also:

Life cycle of reference-counted objects

whenConsumed

CompletableFuture<Void> whenConsumed()

Returns a CompletableFuture which is completed when all elements written so far have been consumed by the Subscriber.

Returns:

the future which completes successfully when all elements written so far have been consumed, or exceptionally when the StreamMessage has been closed unexpectedly.

close

void close()

Closes the StreamMessage successfully. Subscriber.onComplete() will be invoked to signal that the Subscriber has consumed the stream completely.

close

void close(Throwable cause)

Closes the StreamMessage exceptionally. Subscriber.onError(Throwable) will be invoked to signal that the Subscriber did not consume the stream completely.