title: OpenMPI: package mpi does not exist
body: <p>I work with OpenMPI. I want to run Hello.java and Ring.java from the examples  <a href="https://github.com/open-mpi/ompi/tree/master/examples" rel="nofollow">here</a> . 
  I compile Hello.java with this line:</p>
  
  <pre><code>javac Hello.java
  </code></pre>
  
  <p>Then I can run it with mpirun. </p>
  
  <p>But when I compile it, I get this error:</p>
  
  <pre><code>Hello.java:25: error: package mpi does not exist
  import mpi.*;
  ^
  Hello.java:28: error: cannot find symbol
      static public void main(String[] args) throws MPIException {
                                                    ^
    symbol:   class MPIException
    location: class Hello
  Hello.java:31: error: cannot find symbol
      MPI.Init(args);
      ^
    symbol:   variable MPI
    location: class Hello
  Hello.java:33: error: package MPI does not exist
      int myrank = MPI.COMM_WORLD.getRank();
                      ^
  Hello.java:34: error: package MPI does not exist
      int size = MPI.COMM_WORLD.getSize() ;
                    ^
  Hello.java:37: error: cannot find symbol
      MPI.Finalize();
      ^
    symbol:   variable MPI
    location: class Hello
  6 errors
  </code></pre>
  
  <p>can anyone tell me where I can find MPI package? or how can I resolve this problem?</p>
  
  <p>PS: I run the file hello_c.c with mpicc and mpic++ without any problem.</p>