org.eclipse.jetty.spdy.parser.WindowUpdateBodyParser Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2018 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.spdy.parser;
import java.nio.ByteBuffer;
import org.eclipse.jetty.spdy.frames.WindowUpdateFrame;
public class WindowUpdateBodyParser extends ControlFrameBodyParser
{
private final ControlFrameParser controlFrameParser;
private State state = State.STREAM_ID;
private int cursor;
private int streamId;
private int windowDelta;
public WindowUpdateBodyParser(ControlFrameParser controlFrameParser)
{
this.controlFrameParser = controlFrameParser;
}
@Override
public boolean parse(ByteBuffer buffer)
{
while (buffer.hasRemaining())
{
switch (state)
{
case STREAM_ID:
{
if (buffer.remaining() >= 4)
{
streamId = buffer.getInt() & 0x7F_FF_FF_FF;
state = State.WINDOW_DELTA;
}
else
{
state = State.STREAM_ID_BYTES;
cursor = 4;
}
break;
}
case STREAM_ID_BYTES:
{
byte currByte = buffer.get();
--cursor;
streamId += (currByte & 0xFF) << 8 * cursor;
if (cursor == 0)
{
streamId &= 0x7F_FF_FF_FF;
state = State.WINDOW_DELTA;
}
break;
}
case WINDOW_DELTA:
{
if (buffer.remaining() >= 4)
{
windowDelta = buffer.getInt() & 0x7F_FF_FF_FF;
onWindowUpdate();
return true;
}
else
{
state = State.WINDOW_DELTA_BYTES;
cursor = 4;
}
break;
}
case WINDOW_DELTA_BYTES:
{
byte currByte = buffer.get();
--cursor;
windowDelta += (currByte & 0xFF) << 8 * cursor;
if (cursor == 0)
{
windowDelta &= 0x7F_FF_FF_FF;
onWindowUpdate();
return true;
}
break;
}
default:
{
throw new IllegalStateException();
}
}
}
return false;
}
private void onWindowUpdate()
{
WindowUpdateFrame frame = new WindowUpdateFrame(controlFrameParser.getVersion(), streamId, windowDelta);
controlFrameParser.onControlFrame(frame);
reset();
}
private void reset()
{
state = State.STREAM_ID;
cursor = 0;
streamId = 0;
windowDelta = 0;
}
private enum State
{
STREAM_ID, STREAM_ID_BYTES, WINDOW_DELTA, WINDOW_DELTA_BYTES;
}
}