Java and C++

[bobby reddy]

Hello everyone,
how can core java or normal java application communicate with C++ programs?

thanks,
bobby

[Ernest Friedman-Hill]

Many ways!

1) One program can execute the other as a separate program, and they can interact with the other program's command line.

2) Two programs can communicate via a TCP socket.

3) A Java program can directly invoke C++ code right inside the Java program by using a tool called the Java Native Interface (JNI) (see here.)

[Rob Spoor]

Originally posted by Ernest Friedman-Hill:
2) Two programs can communicate via a TCP socket.

Shared memory, named pipes and files are also possibilities, although TCP is the easiest to use in Java while still avoiding the synchronization problems you'll get with the files (since Java may be able to read them even if the C++ is writing to them).

[Peter Chase]

Originally posted by Ernest Friedman-Hill:
A Java program can directly invoke C++ code right inside the Java program by using a tool called the Java Native Interface (JNI) (see here.)

JNI works both ways: you can use it to call Java from C++, too.

Note that Java cannot be called without a JVM running to host the Java. However, JNI includes the Invocation Interface, for starting a JVM from C++.

[Ilja Preuss]

There are a lot more possibilities - in one occasion, we use Windows Messaging Service, for example.

I think it would make more sense to come from the other direction: what are your requirements?