--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/dancres/io/AnnotatingObjectOutputStream.java	Sat Mar 21 11:00:06 2009 +0000
@@ -0,0 +1,97 @@
+package org.dancres.io;
+
+import java.io.IOException;
+import java.io.ObjectOutputStream;
+import java.io.OutputStream;
+
+import java.rmi.server.RMIClassLoader;
+
+import java.util.WeakHashMap;
+import java.util.logging.Logger;
+import java.util.logging.Level;
+
+/**
+   Serializes a set of objects, separting annotations into one stream and
+   object data into another.  This is useful in various situations including
+   equality checking where one may not wish to include the codebase
+   annotations.
+ */
+public class AnnotatingObjectOutputStream extends ObjectOutputStream {
+    private static final Logger theLogger =
+        Logger.getLogger("org.dancres.io.AnnotatingObjectOutputStream");
+
+    private static final WeakHashMap theCachedCodebases = new WeakHashMap();
+
+    private ObjectOutputStream theAnnotations;
+
+    public AnnotatingObjectOutputStream(OutputStream anObjStream,
+                                        OutputStream anAnnStream)
+        throws IOException {
+
+        super(anObjStream);
+        theAnnotations = new ObjectOutputStream(anAnnStream);
+    }
+
+    protected void annotateClass(Class aClass) throws IOException {
+        // addAnnotation(RMIClassLoader.getClassAnnotation(aClass));
+        if (theLogger.isLoggable(Level.FINEST)) {
+            theLogger.log(Level.FINEST, "Annotating " + aClass.getName() +
+                ".class with " + getCodebase(aClass));
+        }
+
+        addAnnotation(getCodebase(aClass));
+    }
+
+    protected void annotateProxyClass(Class aClass) throws IOException {
+        // addAnnotation(RMIClassLoader.getClassAnnotation(aClass));
+        if (theLogger.isLoggable(Level.FINEST)) {
+            theLogger.log(Level.FINEST, "Annotating proxy " + aClass.getName() +
+                ".class with " + getCodebase(aClass));
+        }
+
+        addAnnotation(getCodebase(aClass));
+    }
+
+    private String getCodebase(Class aClass) {
+        CodebaseHolder myCodebase;
+
+        synchronized(theCachedCodebases) {
+            myCodebase =
+                    (CodebaseHolder) theCachedCodebases.get(aClass);
+
+            if (myCodebase == null) {
+                myCodebase =
+                        new CodebaseHolder(RMIClassLoader.getClassAnnotation(aClass));
+                theCachedCodebases.put(aClass, myCodebase);
+            }
+        }
+
+        return myCodebase.getCodebase();
+    }
+
+    private void addAnnotation(String anAnnotation) throws IOException {
+        theAnnotations.writeObject(anAnnotation);
+    }
+
+    public void flush() throws IOException {
+        super.flush();
+        theAnnotations.flush();
+    }
+
+    public void close() throws IOException {
+        super.close();
+        theAnnotations.close();
+    }
+
+    private static class CodebaseHolder {
+        private String theCodebase;
+
+        CodebaseHolder(String aCodebase) {
+            theCodebase = aCodebase;
+        }
+
+        public String getCodebase() {
+            return theCodebase;
+        }
+    }
+}