Would Java programmers hire C# programmers?

TomWij, it depends on the potential employer. If the employer understand the interchangeability of knowledge among engineers, it should not be a problem. Unfortunately, most aren't like that. In fact, I only know of one employer in the commercial sector that does that. Government agencies and defense contractors are usually much better at this. That is, they give you a chance to apply for a job on X technology provided that you can demonstrate proficiency in a similar technology (or that you have very strong engineering skills.)

My suggestion to you is not to worry about interview questions. It is a hit and miss. Either you get an interview with silly language questions that you can pass just by looking at the Javadocs (if you are good enough.) Or you get hammered with a real interview that you cannot possibly answer without having actual work experience.

For the later, the reason being is that in Java development, it is a lot more than just knowing the language. You have to be proficient in the JEE architecture stack (sometimes down to the database/Java interoperability... typically Oracle or MySQL); you need to know either the standards (EJB 3.x, JSF, JPA) or alternate stacks (Spring, etc.)

I have no doubt that if you are good in C# you would have no problem doing well in Java. The problem is convincing employers that you are good without having experience. It is the stupid chicken-n-egg problem that plagues everybody in the software industry, not just us Java and C# developers.

If you feel that you really need to switch to Java, but have a hard time getting a break w/o work experience because employers are simply too stupid to give you one, I'd suggest you work on becoming a Sun certified Professional.

I'd suggest you work your way through the following, at a minimum:

Sun Certified Java Programmer (SCJP) Sun Certified Web Component Developer (SCWCD) Sun Certified Developer for Java Web Services (SCDJWS)

These three should start helping you a bit. However, I would strongly suggest you go for the following as well:

Sun Certified Business Component Developer (SCBCD) Sun Certified Enterprise Architect (SCEA)

It is not a guarantee, but it will improve your odds. Taking the first 3 should take about a year. All five should take about 2. So you have to look at it as a mid-term investment. Even if you land a Java job without completing these, I'd suggest you do.

You can always try with defense contractors looking for Java developers (Lockheed Martin, General Dynamics, Northon Grumman, Honeywell, Harris) or with government agencies (DOD, DOE, DOT, which you canfind at usajobs.gov... if you are in the USA, though.). They'll be far more willing to take a good C# programmer for a Java position than a commercial entity.

Then, you earn your bones on the Java field and you are in.

I do wish you luck you get a chance to work on Java. Although the JVM and .NET have a lot in c

How well do you know particular C# APIs and particular Java APIs? Though the languages are similar, I've found that it takes time to learn new APIs (in particular the Java XML APIs.)

If you made the java->C# switch, why couldn't you do the inverse?

Of course it's possible, C# and Java have many points in common, as well as many differences.

On a java-job interview, I would concentrate on what makes java stronger against, for example, C# or other similar languages.

I would definitely hire you to do Java work after coming from a C# background (I'll probably have to do the opposite for a project that's coming up since only Java people are available). The question is: do you do OO coding? Java and C# are syntactically very similar.

If you manage to get an interview, you may want to express this concern at the interview, with the obvious defense that you've done your homework. You should be well-versed in the differences between the two. One example are the naming conventions and how they differ between the two. For instance, in C# methods are Method and in Java they are always method. Look at getters and setters, and how generics have been worked into both languages (IMHO, kind of sad how weird they are in Java). There are many other similar points, and a lot of great docs comparing the two.

I agree with opinions of everyone so far. I was trained as Java developer and I've working in java commerically. These days I working with C#. I'll go back to java if job is available. However .NET is a wonderful platform. Java and C# are interchangeable.

Absolutely not. We hate you.

Just kidding. C# and Java are very much alike and there's absolutely no reason why you wouldn't hire a C# programmer. Well, unless you are specifically looking for an experience Java programmer. But in general the transition is fairly easy and I think it is even easier from C# to Java since you basically just need to forget some of the more modern features of C# (introduced by C#1&2). Of course it takes some time to get familiar with the API, but that shouldn't be an issue.
I myself started as Java programmer and now I'm doing both. I find switching from language to another to be very easy.

In my opinion (and that's worth all of $0.02) if you can code in C# you can code in JAVA. Software is software to an extent, I don't want to bring in some GURU that claims to be a JAVA master but can't learn C# down the road.

What if we need to use a new framework or tool-kit down the road? I want someone that can pick up things on the fly if need be.