How to include Source Code by pointing to a File Path (recursively)

To expand on my comment, you could always do something like this:

\documentclass{article}
\usepackage{pgffor}
\usepackage{listings}
\begin{document}

\foreach \java in  {hello, hello} {
   \begin{figure}[htpb]
        \lstinputlisting[language=java]{\java.java}
        \caption{Source code for \textsf{\java.java}}
     \label{fig:\java}
   \end{figure}
}

\end{document}

with output:

This does not recursively search for files but it will update when the source files change and it does minimize what you have to type by only requiring you to add the file names to the loop.

The MWE is more for proof of concept as you'd probably want to tweak the formatting and layout of the code. Personally, I'd never use figure, or floats in general, as I like text/environments to appear where I type them:). I just checked and, as I suspected, using figure causes problems when the source file is too long to fit on one page.