Class Plex2

  • All Implemented Interfaces:
    CSProcess

    public final class Plex2
    extends java.lang.Object
    implements CSProcess
    Fair multiplexes two Object streams into one.

    Process Diagram

        in0  _______
       -->--|       | out
        in1 | Plex2 |-->--
       -->--|_______|
     

    Description

    Plex2 is a process whose output stream is a fair multiplexing of its input streams. It makes no assumptions about the traffic patterns occuring on the input streams and ensures that no input stream will be starved by busy siblings. It guarantees that if an input stream has data pending, no other stream will be serviced twice before that data is serviced.

    Channel Protocols

    Input Channels
    in0, in1 java.lang.Object The input streams.
    Output Channels
    out java.lang.Object The multiplexed output stream.

    Example

    The following example shows how to use Plex2 in a small program. The program also uses some of the other plugNplay processes.
     import org.jcsp.lang.*;
     import org.jcsp.plugNplay.*;
     
     public class Plex2Example {
     
       public static void main (String[] argv) {
     
         final One2OneChannel[] a = Channel.one2oneArray (2);
         final One2OneChannel[] b = Channel.one2oneArray (2);
         final One2OneChannel c = Channel.one2one ();
     
         new Parallel (
           new CSProcess[] {
             new Fibonacci (a[0].out ()),
             new Squares (a[1].out ()),
             new Sign ("Fibonacci ", a[0].in (), b[0].out ()),
             new Sign ("              Squares ", a[1].in (), b[1].out ()),
             new Plex2 (b[0].in (), b[1].in (), c.out ()),
             new Printer (c.in (), "", "\n")
           }
         ).run ();
     
       }
     
     }
     

    Implemntation Note

    For information, here is the run method for this process:
       public void run () {
         AltingChannelInput[] input = {in0, in1};         // in0 and in1 are the input channels
         Alternative alt = new Alternative (input);
         while (true) {
           out.write (input[alt.fairSelect ()].read ());  // out is the output channel
         }
       }
     
    See Also:
    Plex, Multiplex
    • Constructor Detail

      • Plex2

        public Plex2​(AltingChannelInput in0,
                     AltingChannelInput in1,
                     ChannelOutput out)
        Construct a new Plex2 process with the input channels in0 and in1 and the output channel out. The ordering of the input channels makes no difference to the behaviour of this process.
        Parameters:
        in0 - an input channel
        in1 - an input channel
        out - the output channel
    • Method Detail

      • run

        public void run()
        The main body of this process.
        Specified by:
        run in interface CSProcess