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 items 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.
Please see the documentation for more information.
Constructor and description |
---|
Pump
(java.lang.Object delegate) |
Type | Name and description |
---|---|
java.lang.Object |
getDelegate() |
int |
numberPumped() Return the total number of items pumped by this pump. |
static Pump |
pump(ReadStream<T> rs, WriteStream<T> ws) Create a new Pump with the given ReadStream and WriteStream |
static Pump |
pump(ReadStream<T> rs, WriteStream<T> ws, int writeQueueMaxSize) Create a new Pump with the given ReadStream and WriteStream and
writeQueueMaxSize |
Pump |
setWriteQueueMaxSize(int maxSize) Set the write queue max size to maxSize |
Pump |
start() Start the Pump. |
Pump |
stop() Stop the Pump. |
Methods inherited from class | Name |
---|---|
class java.lang.Object |
java.lang.Object#wait(long, int), java.lang.Object#wait(long), java.lang.Object#wait(), java.lang.Object#equals(java.lang.Object), java.lang.Object#toString(), java.lang.Object#hashCode(), java.lang.Object#getClass(), java.lang.Object#notify(), java.lang.Object#notifyAll() |
Return the total number of items pumped by this pump.
Create a new Pump
with the given ReadStream
and WriteStream
rs
- the read streamws
- the write stream Create a new Pump
with the given ReadStream
and WriteStream
and
writeQueueMaxSize
rs
- the read streamws
- the write streamwriteQueueMaxSize
- the max size of the write queue Set the write queue max size to maxSize
maxSize
- the max sizeStart the Pump. The Pump can be started and stopped multiple times.
Stop the Pump. The Pump can be started and stopped multiple times.