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 {@link ReadStream} is paused, and a WriteStream.drainHandler() is set on the WriteStream. When the WriteStream has processed half of its backlog, the WriteStream.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 {@link org.vertx.java.core.file.AsyncFile} (todo), or from {@link org.vertx.java.core.net.NetSocket} (todo) to a {@link org.vertx.java.core.http.WebSocket} (todo).

Instances of this class are not thread-safe.

  • Pump
    • Basic
      • Identifiable
      • Object
        • Anything

no subtypes hierarchy

Pump(ReadStream rs, WriteStream ws, Integer? maxSize = null)
  • maxSize = null
bytesPumpedshared Integer bytesPumped

Return the total number of bytes pumped by this pump.

Inherited Attributes
Attributes inherited from: Object
hash, string
setWriteQueueMaxSizeshared Pump setWriteQueueMaxSize(Integer maxSize)

Set the write queue max size to `maxSize

startshared Pump start()

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

stopshared Pump stop()

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

Inherited Methods
Methods inherited from: Object