net.mograsim.machine/src/net/mograsim/machine/mi/StandardMicroInstructionMemory.java

   1 package net.mograsim.machine.mi;
   2
   3 import java.util.HashSet;
   4
   5 import net.mograsim.machine.MemoryObserver;
   6 import net.mograsim.machine.standard.memory.MemoryException;
   7
   8 public class StandardMicroInstructionMemory implements MicroInstructionMemory
   9 {
  10         private MicroInstruction[] data;
  11         private MicroInstructionMemoryDefinition definition;
  12         private HashSet<MemoryObserver> observers = new HashSet<>();
  13
  14         public StandardMicroInstructionMemory(MicroInstructionMemoryDefinition definition)
  15         {
  16                 if (definition.size() > Integer.MAX_VALUE)
  17                         throw new MemoryException("Size of MicroInstructionMemory must be an int, not a long");
  18                 this.definition = definition;
  19                 data = new MicroInstruction[(int) definition.size()];
  20         }
  21
  22         private int translate(long address)
  23         {
  24                 return (int) (address - definition.getMinimalAddress());
  25         }
  26
  27         @Override
  28         public MicroInstruction getCell(long address)
  29         {
  30                 int translatedAddress = translate(address);
  31                 MicroInstruction actual = data[translatedAddress];
  32                 if (actual == null)
  33                         actual = data[translatedAddress] = definition.getMicroInstructionDefinition()
  34                                         .createDefaultInstruction(() -> notifyObservers(address));
  35                 return actual;
  36         }
  37
  38         @Override
  39         public void setCell(long address, MicroInstruction data)
  40         {
  41                 this.data[translate(address)] = data;
  42                 notifyObservers(address);
  43         }
  44
  45         @Override
  46         public void registerObserver(MemoryObserver ob)
  47         {
  48                 observers.add(ob);
  49         }
  50
  51         @Override
  52         public void deregisterObserver(MemoryObserver ob)
  53         {
  54                 observers.remove(ob);
  55         }
  56
  57         @Override
  58         public void notifyObservers(long address)
  59         {
  60                 observers.forEach(ob -> ob.update(address));
  61         }
  62
  63         @Override
  64         public MicroInstructionMemoryDefinition getDefinition()
  65         {
  66                 return definition;
  67         }
  68
  69 }