era.mi/src/net/mograsim/logic/core/components/Merger.java

   1 package net.mograsim.logic.core.components;
   2
   3 import java.util.List;
   4
   5 import net.mograsim.logic.core.timeline.Timeline;
   6 import net.mograsim.logic.core.types.BitVector;
   7 import net.mograsim.logic.core.wires.Wire;
   8 import net.mograsim.logic.core.wires.WireObserver;
   9 import net.mograsim.logic.core.wires.Wire.ReadEnd;
  10 import net.mograsim.logic.core.wires.Wire.ReadWriteEnd;
  11
  12 public class Merger extends Component implements WireObserver
  13 {
  14         private ReadWriteEnd out;
  15         private ReadEnd[] inputs;
  16         private int[] beginningIndex;
  17
  18         /**
  19          *
  20          * @param union  The output of merging n {@link Wire}s into one. Must have length = a1.length() + a2.length() + ... + an.length().
  21          * @param inputs The inputs to be merged into the union
  22          */
  23         public Merger(Timeline timeline, ReadWriteEnd union, ReadEnd... inputs)
  24         {
  25                 super(timeline);
  26                 this.inputs = inputs;
  27                 this.out = union;
  28                 this.beginningIndex = new int[inputs.length];
  29
  30                 int length = 0;
  31                 for (int i = 0; i < inputs.length; i++)
  32                 {
  33                         beginningIndex[i] = length;
  34                         length += inputs[i].length();
  35                         inputs[i].addObserver(this);
  36                 }
  37
  38                 if (length != union.length())
  39                         throw new IllegalArgumentException(
  40                                         "The output of merging n WireArrays into one must have length = a1.length() + a2.length() + ... + an.length().");
  41         }
  42
  43         public ReadEnd getInput(int index)
  44         {
  45                 return inputs[index];
  46         }
  47
  48         public ReadEnd getUnion()
  49         {
  50                 return out;
  51         }
  52
  53         @Override
  54         public void update(ReadEnd initiator, BitVector oldValues)
  55         {
  56                 int index = find(initiator);
  57                 int beginning = beginningIndex[index];
  58                 out.feedSignals(beginning, inputs[index].getValues());
  59         }
  60
  61         private int find(ReadEnd r)
  62         {
  63                 for (int i = 0; i < inputs.length; i++)
  64                         if (inputs[i] == r)
  65                                 return i;
  66                 return -1;
  67         }
  68
  69         public ReadEnd[] getInputs()
  70         {
  71                 return inputs.clone();
  72         }
  73
  74         @Override
  75         public List<ReadEnd> getAllInputs()
  76         {
  77                 return List.of(inputs);
  78         }
  79
  80         @Override
  81         public List<ReadWriteEnd> getAllOutputs()
  82         {
  83                 return List.of(out);
  84         }
  85 }