如何从Ubuntu中的Java程序运行C可执行文件

Question

I am unable to run c executable file from a java program in ubuntu.

I created executable file using following command :

gcc ex.c -o process

In java program i tried everything i could find but no result.

Runtime.getRuntime().exec("/home/cori/Desktop/process.exe);

another method

Runtime rt = Runtime.getRuntime();
Process proc = rt.exec("process");

Please suggest.

Answer 1

*nix like systems doesn't uses the *.exe postfix for executable files.

Runtime.getRuntime().exec("/home/cori/Desktop/process")

should work fine. But I still don't get what result you want to get. The only things you can get from a Process class is few streams, and its return status. Which for you c program should be 0. (if you returned 0 end the end of your source code).

And: The 2 methods you mentioned are the same. Just the first uses something call Method chaining :)

Answer 2

I am assuming you have access to the C code because I see you trying to compile it.

Have you considered using Java Native Inteface? Java allows you to call non-Java code, usually referred to as native code.

You have to follow a sequence of steps to get it work. See an example here http://www3.ntu.edu.sg/home/ehchua/programming/java/JavaNativeInterface.html

1. Create a Java class with native method
2. Load the library which implements the method
3. Invoke the native method from Java
4. Use javah utility to generate the header file
5. Create c code to implement the java stub method
6. compile c program tp create .so or .dll (depending on OS)
7. Set LD_LIBRARY_PATH
8. Run the Java code

It is a long process and It takes some trial and error to get it right. But once you figure it out it is a really powerful tool. This is a very old feature of Java, so there are lots of resources online.