Translating/converting/compiling from C++ to C, and from C# to Java

[finlay666]

Long story short I'm looking to port some of my apps across format (Windows Mobile to Android and another side project potentially to another platform)

Are there compilers that will compile/translate C# and output a java file? I dont care on the readability for this one, as it's a straight port I plan to do then change the important calls... it's mostly refactored nicely already

Other one is a cross platform port from C++ to C for linux, most of the work has been done already (it was badly written in Java!) but still interested if there is something that can save the work

[scaryjim]

Can't see C# to Java working as the Libraries and interfaces are completely different: unless you haven't used a single object in your script you'll need to rewrite it to use the Java equivalents of the .NET classes. Depending on what your app does that could be a pain the rear, frankly - for some tasks there is no direct .NET - java translation and you have to (slightly) rework the implementation. Also AFAIK Android uses a number of non-standard libraries so you'd need a special C# -> Android interpreter.

tbh I think you'll be much better off just rewriting in Java. Is this a personal project or proper paid work?

[CrazyMonkey]

tbh I think you'll be much better off just rewriting in Java.

Agreed.

[aidanjt]

C++ is 'C with classes', the problem isn't with the C++ working on Linux, that'll work fine, the problem is whatever libraries you may use, and as far as I know, there is no MFC->Qt converter because it requires intelligence to understand the difference between the two environments to make the changes.

[Mblaster]

Can't see C# to Java working as the Libraries and interfaces are completely different: unless you haven't used a single object in your script you'll need to rewrite it to use the Java equivalents of the .NET classes. Depending on what your app does that could be a pain the rear, frankly - for some tasks there is no direct .NET - java translation and you have to (slightly) rework the implementation. Also AFAIK Android uses a number of non-standard libraries so you'd need a special C# -> Android interpreter.

tbh I think you'll be much better off just rewriting in Java. Is this a personal project or proper paid work?

Pretty much what he said

Even if you could find a C# to Java translation tool, there are lots of domain specific classes/interfaces used so translating that couldn't be done automatically. Things like GUIs and any system calls would be too different for any simple translation between the two platforms.

Since C# and Java are pretty similar in syntax you may find sections of the code can just be copied over and given minor edits, but you're still going to have to restructure and rewrite a significant amounts of the program.

[yamangman]

I imagine writing a piece of software which could corralate suggestions for the difference in types between the C# and Java libraries would be difficult enough, without a converting the code as well. I mean take C#.NET IComparable interface for example, a commonly used interface. How would you cleanly convert implementors to Java's Comparable<T> type? It would require a lot of rigourous code to do that cleanly, and that is just one extremely simple interface from thousands of types. A C++ to C converter makes even less sense.

[TheAnimus]

I imagine writing a piece of software which could corralate suggestions for the difference in types between the C# and Java libraries would be difficult enough, without a converting the code as well. I mean take C#.NET IComparable interface for example, a commonly used interface. How would you cleanly convert implementors to Java's Comparable<T> type? It would require a lot of rigourous code to do that cleanly, and that is just one extremely simple interface from thousands of types. A C++ to C converter makes even less sense.

Actually that one would be easy (What with IComparable<T> n all........).

Is it possible to use mono on the target device?

[yamangman]

Actually that one would be easy (What with IComparable<T> n all........).

Is it possible to use mono on the target device?

Java has no 'comparable' non-generic Comparable interface as far as I'm aware. Object could be its type but that defeats its' purpose. Like you say it's a 'easy' example, but one of many thousands in total and probably many hundreds where there is no corollary whatsoever.

[finlay666]

Is it possible to use mono on the target device?

I don't think Android supports Mono, the WM app used .Net CF 3.0 (or 3.5) for the xml which should already be present

The C++ one is fairly straightforward, I have already translated from java to C++ (there is a translator available for it)

Personal projects, I wrote the app in my sig for a competition and wanted to get some experience with android so figured (as I have done a bit of java already and it's another OO language) to port my app to. Benefit is dev tools are free (like Windows Mobile but unlike iFail) and I don't have to release to the app store so save money there

[scaryjim]

... and wanted to get some experience with android ...

Fair enough - I was considering offering assistance in porting it, but if you want experience that's probably not going to interest you!

[finlay666]

Fair enough - I was considering offering assistance in porting it, but if you want experience that's probably not going to interest you!

Nah it's ok, it'll be for a contest no doubt anyway, good way to get visibility it seems (won a Samsung NC10 netbook with the other entry)

Working with ARM stuff in C atm, that isnt too nice dealing with radio transmitters for communication etc

[scaryjim]

... won a Samsung NC10 netbook with the other entry ...

Nice one! Maybe I should look into doing some of these competitions...

[directhex]

I don't think Android supports Mono

http://www.koushikdutta.com/2009/11/...n-android.html

the problem is tools & polish. actually, try doing a search on the google market for "mono" for a proof-of-concept.

[scaryjim]

I don't think I'm going to bother learning new programming languages anymore - if I wait long enough someone'll make the ones I do know work on everything anyway...