StringBuffer buf = new StringBuffer();
chain.addLast("A", new TestCommand(buf, 'A'));
chain.addLast("B", new TestCommand(buf, 'B'));
chain.addLast("C", new TestCommand(buf, 'C'));
new ChainedIoHandler(chain).messageReceived(new DummySession(), null);
Assert.assertEquals("ABC", buf.toString());
}