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().createDefaultInstruction();
  34                 return actual;
  35         }
  36
  37         @Override
  38         public void setCell(long address, MicroInstruction data)
  39         {
  40                 this.data[translate(address)] = data;
  41                 notifyObservers(address);
  42         }
  43
  44         @Override
  45         public void registerObserver(MemoryObserver ob)
  46         {
  47                 observers.add(ob);
  48         }
  49
  50         @Override
  51         public void deregisterObserver(MemoryObserver ob)
  52         {
  53                 observers.remove(ob);
  54         }
  55
  56         @Override
  57         public void notifyObservers(long address)
  58         {
  59                 observers.forEach(ob -> ob.update(address));
  60         }
  61
  62         @Override
  63         public MicroInstructionMemoryDefinition getDefinition()
  64         {
  65                 return definition;
  66         }
  67
  68 }