No, you ask for what you want. "Person X has air in their Aorta, I need a doctor quickly, this is an emergency!"
Similarily if the person with the Java question needed an expert to do something for them they could have asked: "Any Java expert here willing to take a job? You can contact me at foo@bar.org"
Your question is valid if you're the doctor yourself and just need a piece of knowledge to fix things yourself (as isn't uncommon in the programming world)
Don't say presumptious, lazy shit that walls people out like, "Is there a doctor in the house?"
Instead, say, "Help! How do I bleed (so to speak) bubbles of air out of someone's aorta?"