era.mi/src/era/mi/logic/components/Merger.java

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