channel.getInputStream() should warn if the channel has already connected

[pshem]

We recently fixed a bug in our code where we were doing two things in the wrong order, which would lead to a race condition.

Examples, such as

jsch/examples/ScpTo.java

Lines 43 to 45 in c6970b8

	InputStream in = channel.getInputStream();
	channel.connect();

show you should first grab an InputStream and then connect.

Our code had:

channel.connect();
InputStream in = channel.getInputStream();
List<String> response = readStream(in);

It mostly worked, but would occasionally fail, mostly when testing connections between two fastest machines located nearby.

Would it be possible to log a warning when you getInputStream() but the channel has already connected, or is that a valid scenario in some circumstances?

[norrisjeremy]

Hi @pshem,

I've included a change to add some logger warnings when getInputStream() or getExtInputStream() are called after connect() as part of #431.

Thanks,
Jeremy

[pshem]

Thank you very much - my older self would have noticed (we'd spent a week looking over debug level messages from JSch to figure out what was wrong before reading the documentation 🥲 )