Tell him to learn both but Ruby first. When you start programming, you're learning as much about the environment (OS, files, network) as you are the language. R

Tell him to learn both but Ruby first. When you start programming, you're learning as much about the environment (OS, files, network) as you are the language. Ruby will help keep that simple. Then, Java will give exposure to a "harder" language with an enormous ecosystem, plus the JVM itself. Knowing both Ruby and Java should make him eminently employable.