Once, when I was myself a fairly junior Java developer, I gave a candidate what I thought was a rather basic exercise, geared to a level of knowledge that could be gleaned from the first few chapters of most introductory Java books: take two integers from the command-line arguments and print their sum to the standard output. If possible exceptions were handled, even better, but printing a sum would have been enough. I supplied the candidate with a machine, a simple text editor, the Java SDK, and the standard API documentation.
I left him alone to work on it for 45 minutes. Although he claimed to have worked with Java in his last job, he had no idea how to proceed.
I think it's entirely reasonable to expect an experienced programmer to have basic skills in reading documentation, writing simple code, and running programs on the target platform.