C++ to Java Converter FAQ

Q: Are the original C++ files altered in any way?

Your existing code is left completely intact. The new Java files are output to the new location that you specify.

Q: What version of C++ is converted?

We attempt to convert as much as possible and are continually updating the converter to handle newer C++ features. However, many new C++ features have no Java equivalent so the output will require adjustments.

Q: What is the conversion accuracy?

Our accuracy is very high, but there will be significant adjustments required for all but the most trivial conversions. There are no direct equivalents for some aspects of C++. Read the rest of the FAQ to get an idea of a few things that are not converted. C++ to Java Converter is intended to reduce the amount of work you'll have to do to convert code to Java, but it is just the first step.

You should not attempt to convert code that is heavily dependent on pointer arithmetic or template metaprogramming since these features are only practical in C++.

Q: What about function pointers?

C++ to Java Converter converts function pointer typedefs to functional interfaces.

Q: What about STL Containers?

C++ to Java Converter converts references to most STL container types, such as std::vector. A few methods of these containers that have no equivalent are not converted.

Q: Is C++/CLI code converted?

No. Despite the name, C++/CLI has very little in common with C++.

Q: What about C++ UI code?

The converter does not convert C++ UI types due to the lack of similarity between these types and Java UI types.

Q: What are the most common adjustments necessary after conversion?

Most C/C++ library function calls are not converted. However, we do convert a subset of the C-based string, keyboard I/O, math, and utility function calls, and some of the C++ keyboard I/O methods, STL-based string class methods, and most STL containers.
Pointer arithmetic has no good equivalent in Java.
Some pointer and address manipulation may remain in the converted code.
Code that is extremely dependent on the preprocessor may result in more conversion issues.
Multiple inheritance is not converted since it is not available in Java.
Most operator overloads are converted, but a few operator overloads cannot be converted and are marked with a comment.
Some function pointers cannot be converted to Java. Only function pointer typedefs are converted to Java functional interfaces.
Since Java lacks a preprocessor, all code dependent on conditional compilation needs to be refactored so that the functionality can be achieved in other ways.
C++ templates are converted to, but are only roughly equivalent to, Java generics. These may require further attention.
C++ template metaprogramming and variadic templates have no equivalent in Java.
Bit-by-bit copying of objects via the assignment operator is not the default in Java. We attempt to detect these cases and convert the assignment to a call to either the copy constructor (if used in a variable initialization) or the converted assignment operator overload (which is converted to a 'copyFrom' method) and also provide a 'Warning' comment.
Java does not allow embedded assembly instructions. These are marked with a comment.
There is no equivalent to friend functions or friend classes in Java. These are marked with a comment.
Unions and bit fields have no elegant equivalent in Java. Unions are commented out with a 'task' note.

Additional Resources

Java and C++ comparison and equivalents chart