io.vertx.core.streams.impl

Class PumpImpl<T>

java.lang.Object

io.vertx.core.streams.impl.PumpImpl<T>

All Implemented Interfaces:

Pump

public class PumpImpl<T>
extends Object
implements Pump

Pumps data from a ReadStream to a WriteStream and performs flow control where necessary to prevent the write stream buffer from getting overfull.

Instances of this class read bytes from a ReadStream and write them to a WriteStream. If data can be read faster than it can be written this could result in the write queue of the WriteStream growing without bound, eventually causing it to exhaust all available RAM.

To prevent this, after each write, instances of this class check whether the write queue of the WriteStream is full, and if so, the ReadStream is paused, and a drainHandler is set on the WriteStream. When the WriteStream has processed half of its backlog, the drainHandler will be called, which results in the pump resuming the ReadStream.

This class can be used to pump from any ReadStream to any WriteStream, e.g. from an HttpServerRequest to an AsyncFile, or from NetSocket to a WebSocket.

Instances of this class are not thread-safe.

Author:

Tim Fox

Constructor Summary

Constructors

Constructor and Description
PumpImpl(ReadStream<T> rs, WriteStream<T> ws)
PumpImpl(ReadStream<T> rs, WriteStream<T> ws, int maxWriteQueueSize) Create a new Pump with the given ReadStream and WriteStream.

Method Summary

Modifier and Type	Method and Description
int	numberPumped() Return the total number of elements pumped by this pump.
PumpImpl	setWriteQueueMaxSize(int maxSize) Set the write queue max size to maxSize
PumpImpl	start() Start the Pump.
PumpImpl	stop() Stop the Pump.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.vertx.core.streams.Pump

pump, pump

Constructor Detail

PumpImpl

public PumpImpl(ReadStream<T> rs,
                WriteStream<T> ws,
                int maxWriteQueueSize)

Create a new Pump with the given ReadStream and WriteStream. Set the write queue max size of the write stream to maxWriteQueueSize

PumpImpl

public PumpImpl(ReadStream<T> rs,
                WriteStream<T> ws)

Method Detail

setWriteQueueMaxSize

public PumpImpl setWriteQueueMaxSize(int maxSize)

Set the write queue max size to maxSize

Specified by:

setWriteQueueMaxSize in interface Pump

Parameters:

maxSize - the max size

Returns:

a reference to this, so the API can be used fluently

start

public PumpImpl start()

Start the Pump. The Pump can be started and stopped multiple times.

Specified by:

start in interface Pump

Returns:

a reference to this, so the API can be used fluently

stop

public PumpImpl stop()

Stop the Pump. The Pump can be started and stopped multiple times.

Specified by:

stop in interface Pump

Returns:

a reference to this, so the API can be used fluently

numberPumped

public int numberPumped()

Return the total number of elements pumped by this pump.

Specified by:

numberPumped in interface Pump