Issue1120

From CPython:

>>> import socket
>>> socket.socket(socket.AF_INET, socket.SOCK_STREAM)
<socket._socketobject object at 0xb7d71aac>
>>> s = _
>>> s.shutdown(socket.SHUT_RDWR)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 1, in shutdown
socket.error: (107, 'Transport endpoint is not connected')

From Jython:

>>> import socket
>>> socket.socket(socket.AF_INET, socket.SOCK_STREAM)
<socket._socketobject object at 1>
>>> s = _
>>> s.shutdown(socket.SHUT_RDWR)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 1, in shutdown
  File "/home/glyph/Projects/Jython/trunk/jython/dist/Lib/socket.py",
line 810, in shutdown
    assert self.sock_impl
AssertionError

This is indeed a bug, albeit a bug that appears when an invalid series
of operations is carried out on a socket, as noted by the OP.

I will check in a fix today.

Fix checked into trunk and release 2.2.

The illustrated series of operations from the code above will now behave
correctly on jython, i.e. the correct socket.error will be raised, with
the correct errno == errno.ENOTCONN.

Thanks for reporting this bug.