C#, Java, C++, Cobol

[Scarvenger]

1) What´s better to be learned, C# or Java?
2) Any good links for C# and/or Java (like cprogramming.com that helped me alot)?
3) Is C++ and Cobol worth learning? Are they dead in big corporations like Dell and HP?
4) How Cobol runs? Is it needed a runtime like Java, or is it runs natively?
5) Any good analisis(dont know how to write that word sorry) tool for C++, C# and Java? One that i can see the performance and everything.
6) On a big server, is it worth opening a thread for each user connected? If not, what should i do?
7) How to use DLL´s wrotten in C++ in C# and Java? Examples please. And is it worth it? I mean, is it better to rewrite the whole component?

Thank you, and please answer i really need that.

[Wraithan]

1) Flip a coin, I prefer Java, other prefer C#, both run the same way.
2) http://www.google.com
3) C++ is a live language actively being developed still, COBOL is not used so much more other than maintenance of old systems.
4) Haven't played with it.
5) Profilers are commonish for all of those languages.
6) How about you look at the Apache code base, they are a big server application.
7) Language dependent, reinventing the wheel is usually not need if you are trying to use a library via a DLL.

You don't 'really need' an answer you really need to get on google and do some searching. Questions comparing languages are ridiculous if you want to learn a language just do it. For what language is used more in corporations look on job listings for programmers and see for yourself.

Now hit up the link in my sig, become enlightened, and don't get posts like this again.

[Mario F.]

1) Both. Of course. The more, the merrier you and your wallet will be.

2) I don't know... Search the web. Top googlçe hits are usually good links. Good links also provide other good links on their Other Links webpages.

3) C++ worth learning? Of course! Did you haave to ask!? As for Cobol... I don't think so. Unless there is a specific need to maintain legacy software. And until there's a decent compiler for Cobol 2002, the language is basically dormant.

4) Natively! It's one of the oldest languages in existence. Java creator was still being toilet trained!

5) Some. All expensive for windows. I guess there's some free ones for Linux.

6) Depends on so many factors... You would need to be highly specific.

7) It doesn't matter the language a DLL was written in. DLLs offer a common interface.

[CornedBee]

2) http://java.sun.com/ http://www.apache.org/
3) That's a strange question to ask on a board dedicated to C and C++ ...
6) God, no! Threads are far too expensive to have one per client. (Although Apache HTTPD actually dedicates a worker to each keepalive connection - or used to or something. They weren't happy about it, though.) The most scalable solution generally is asynchronous I/O and a thread pool. Async I/O can be a bit tricky, though. Check out http://asio.sf.net/
7) In C#, you use P/Invoke. In Java, the DLLs have to be written to the Java Native Interface. Whether it's worth it depends on various factors. Do you need it to be portable? (DLLs aren't.) Do you need it to be as quick as possible? (Native is a bit faster. But there are costs in crossing the barrier.) How big is the component? (Larger components take longer to convert, obviously.)