git.gag.com Git - sw/motorsim/blob - src/com/billkuker/rocketry/motorsim/ChangeListening.aj

   1 package com.billkuker.rocketry.motorsim;
   2
   3 import java.beans.PropertyChangeEvent;
   4 import java.beans.PropertyChangeListener;
   5 import java.beans.PropertyChangeSupport;
   6 import java.lang.reflect.Method;
   7
   8 public aspect ChangeListening {
   9
  10         public interface Subject {
  11                 // public void addPropertyChangeListener(PropertyChangeListener l);
  12         }
  13
  14         private PropertyChangeSupport Subject.pcs;
  15
  16         public void Subject.addPropertyChangeListener(PropertyChangeListener l) {
  17                 //System.out.println("PCS Added");
  18                 pcs.addPropertyChangeListener(l);
  19         }
  20
  21         public void Subject.removePropertyChangeListener(PropertyChangeListener l) {
  22                 //System.out.println("PCS Removed");
  23                 pcs.addPropertyChangeListener(l);
  24         }
  25
  26         public void Subject.firePropertyChange(PropertyChangeEvent e) {
  27                 pcs.firePropertyChange(e);
  28         }
  29
  30         declare parents: Motor || Grain || Chamber || Nozzle || Fuel implements Subject;
  31
  32         void around(Subject s, Object newVal):
  33                 execution(void Subject+.set*(..)) && target(s) && args(newVal) {
  34                 System.out.println(s);
  35                 String name = thisJoinPointStaticPart.getSignature().getName();
  36                 name = name.replaceFirst("set", "");
  37                 Object old = null;
  38                 try {
  39                         String pre = "get";
  40                         if (newVal instanceof Boolean)
  41                                 pre = "is";
  42                         Method m = s.getClass().getMethod(pre + name);
  43                         old = m.invoke(s);
  44
  45                 } catch (Throwable t) {
  46                         System.err.print("Error getting old value for " + name);
  47                 }
  48                 proceed(s, newVal);
  49                 if (old != newVal) {
  50                         System.out.println(name + " changed from " + old + " to "
  51                                         + newVal);
  52                         s.pcs.firePropertyChange(name, old, newVal);
  53                 }
  54         }
  55
  56         after(Subject s) returning: this(s) && initialization(Subject.new(..)) {
  57                 s.pcs = new PropertyChangeSupport(s);
  58         }
  59 }