commtest.java

MPI for java for Distributed Programming

package mpi.comm;

import mpjdev.*;
import mpjbuf.*;
import mpi.*;
import java.util.Arrays;

public class CommTest {

  public static void main(String args[]) throws Exception {
  }

  public CommTest() {
  }

  public CommTest(String[] args) throws Exception {
    int DATA_SIZE = 100;
    MPI.Init(args);
    int size = MPI.COMM_WORLD.Size();
    int rank = MPI.COMM_WORLD.Rank();

    if(size < 8) {
      if(rank ==0)	    
        System.out.println("comm->CommTest runs with eight processes");
      MPI.COMM_WORLD.Barrier();
      MPI.Finalize();
      return;
    }
    
    /* Creating the new communicator */
    byte byteArray[] = new byte[DATA_SIZE];

    for (int i = 0; i < DATA_SIZE; i++) {
      byteArray[i] = 's';
    }
    
    int[] newIds = {2, 3, 4};
    Intracomm newComm = MPI.COMM_WORLD.Create( (MPI.COMM_WORLD.Group()).Incl 
		    (newIds) );
    int[] newIds1 = {5, 6, 7};
    Intracomm newComm1 = MPI.COMM_WORLD.Create( (MPI.COMM_WORLD.Group()).Incl
		    (newIds1) );

    int[] newIds2 = {0, 1};
    Intracomm newComm2 = MPI.COMM_WORLD.Create( (MPI.COMM_WORLD.Group()).Incl
		    (newIds2) );
   
    int[] newIds3 = {0, 2, 4, 6};
    Intracomm newComm3 = MPI.COMM_WORLD.Create( (MPI.COMM_WORLD.Group()).Incl
		    (newIds3) );

    if (MPI.COMM_WORLD.Rank() == 0 && newComm3.Rank() == 0) {
      newComm3.Send(byteArray,0, DATA_SIZE, MPI.BYTE, 1, 90);
    }
    else if ( MPI.COMM_WORLD.Rank() == 2 && newComm3.Rank() == 1) {
      
      byte byteReadArray[] = new byte[DATA_SIZE];
      
      for (int i = 0; i < DATA_SIZE; i++) {
        byteReadArray[i] = 'x';
      }
      
      //System.out.println("Receving bytes");
      newComm3.Recv(byteReadArray, 0, DATA_SIZE, MPI.BYTE, 0, 90);      

      if (Arrays.equals(byteArray, byteReadArray)) {
	/*       
        System.out.println("\n#################" +
                           "\n <<<<PASSED>>>> " +
                           "\n################");
        */			   
      }
      else {
        System.out.println("\n#################" +
                           "\n <<<<FAILED>>>> " +
                           "\n################");
        //System.exit(0);
      }

    } //end while(true)

    MPI.COMM_WORLD.Barrier();
    
    if(rank == 0) 
      System.out.println("CommTest TEST COMPLETE");

    MPI.Finalize();

  }
}