made future serialized class versions backwards compatible.

3 files changed, 29 insertions, 3 deletions

diff --git a/sources/simulator/VSSimulator.java b/sources/simulator/VSSimulator.java
index aec330e..0a7c6c2 100644
--- a/sources/simulator/VSSimulator.java
+++ b/sources/simulator/VSSimulator.java
@@ -1232,7 +1232,14 @@ public class VSSimulator extends JPanel implements VSSerializable {
     public synchronized void serialize(VSSerialize serialize,
                                        ObjectOutputStream objectOutputStream)
     throws IOException {
+        /** For later backwards compatibility, to add more stuff */
+        objectOutputStream.writeObject(new Boolean(false));
+
         simulatorCanvas.serialize(serialize, objectOutputStream);
+
+        /** For later backwards compatibility, to add more stuff */
+        objectOutputStream.writeObject(new Boolean(false));
+
     }
 
     /* (non-Javadoc)
@@ -1248,8 +1255,15 @@ public class VSSimulator extends JPanel implements VSSerializable {
 
         serialize.setObject("simulator", this);
         serialize.setObject("logging", logging);
+
+        /** For later backwards compatibility, to add more stuff */
+        objectInputStream.readObject();
+
         simulatorCanvas.deserialize(serialize, objectInputStream);
 
+        /** For later backwards compatibility, to add more stuff */
+        objectInputStream.readObject();
+
         updateFromPrefs();
         updateTaskManagerTable();
     }
diff --git a/sources/simulator/VSSimulatorCanvas.java b/sources/simulator/VSSimulatorCanvas.java
index 1b30a51..b521fc7 100644
--- a/sources/simulator/VSSimulatorCanvas.java
+++ b/sources/simulator/VSSimulatorCanvas.java
@@ -1571,6 +1571,9 @@ public class VSSimulatorCanvas extends Canvas
     public synchronized void serialize(VSSerialize serialize,
                                        ObjectOutputStream objectOutputStream)
     throws IOException {
+        /** For later backwards compatibility, to add more stuff */
+        objectOutputStream.writeObject(new Boolean(false));
+
         synchronized (processes) {
             objectOutputStream.writeObject(new Integer(numProcesses));
             for (VSProcess process : processes)
@@ -1578,6 +1581,9 @@ public class VSSimulatorCanvas extends Canvas
         }
 
         taskManager.serialize(serialize, objectOutputStream);
+
+        /** For later backwards compatibility, to add more stuff */
+        objectOutputStream.writeObject(new Boolean(false));
     }
 
     /* (non-Javadoc)
@@ -1591,6 +1597,9 @@ public class VSSimulatorCanvas extends Canvas
         if (VSSerialize.DEBUG)
             System.out.println("Deserializing: VSSimulatorCanvas");
 
+        /** For later backwards compatibility, to add more stuff */
+        objectInputStream.readObject();
+
         int num = ((Integer) objectInputStream.readObject()).intValue();
         logging.clear();
 
@@ -1604,8 +1613,11 @@ public class VSSimulatorCanvas extends Canvas
         }
 
         for (int i = 0; i < num; ++i)
-            processes.get(0).deserialize(serialize, objectInputStream);
+            processes.get(i).deserialize(serialize, objectInputStream);
 
         taskManager.deserialize(serialize, objectInputStream);
+
+        /** For later backwards compatibility, to add more stuff */
+        objectInputStream.readObject();
     }
 }
diff --git a/sources/simulator/VSSimulatorFrame.java b/sources/simulator/VSSimulatorFrame.java
index 2b9042c..ad095c4 100644
--- a/sources/simulator/VSSimulatorFrame.java
+++ b/sources/simulator/VSSimulatorFrame.java
@@ -149,8 +149,8 @@ public class VSSimulatorFrame extends VSFrame {
                     VSSerialize serialize = new VSSerialize();
                     VSSimulator simulator = serialize.openSimulator(
                                                 VSSimulatorFrame.this);
-					if (simulator != null)
-                    	addSimulator(simulator);
+                    if (simulator != null)
+                        addSimulator(simulator);
 
                 } else if (sourceText.equals(
                 finalPrefs.getString("lang.save"))) {