Change dispatching approach: handlers are now part of todoItems.

Instead of dispatching the todo item in function of the DAML node's
local name at todo-handling time, the appropriate todo handler
subclass is now instantiated in the todo deque by dispatching the
creation of the todo item to the appropriate constructor.

1 files changed, 26 insertions, 15 deletions

diff --git a/org/madore/damlengine/TodoElement.java b/org/madore/damlengine/TodoElement.java
index c3dbf0b..f8dcca1 100644
--- a/org/madore/damlengine/TodoElement.java
+++ b/org/madore/damlengine/TodoElement.java
@@ -1,17 +1,18 @@
 package org.madore.damlengine;
 
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
 import java.util.Map;
 import java.util.HashMap;
 import org.w3c.dom.Element;
 
-public class TodoElement extends TodoItem {
+public abstract class TodoElement extends TodoItem {
 
-    protected static Map<String,ElementHandler> damlHandlers;
-    protected static ElementHandler defaultHandler;
+    protected static Map<String,Constructor<? extends TodoElement>> damlConstructors;
 
-    {
-	damlHandlers = new HashMap<String,ElementHandler>();
-	defaultHandler = new DefaultHandler();
+    protected static void initializeDamlConstructors() {
+	// FIXME: this should be a static initializer, but for some reason does not work...
+	damlConstructors = new HashMap<String,Constructor<? extends TodoElement>>();
     }
 
     Element node;
@@ -24,16 +25,26 @@ public class TodoElement extends TodoItem {
 	this.options = options;
     }
 
-    public void dispatch() {
-	ElementHandler handler;
+    public static TodoElement getTodoElement(Element node,
+					     Map<String,Object> context,
+					     Map<String,Object> options) {
+	Constructor<? extends TodoElement> constructor = null;
 	String nsuri = node.getNamespaceURI();
-	if ( nsuri != null && nsuri.equals(DamlEngine.DAML_NS) ) {
-	    handler = damlHandlers.get(node.getLocalName());
-	    if ( handler == null )
-		handler = defaultHandler;
-	} else
-	    handler = defaultHandler;
-	handler.handle(this);
+	if ( damlConstructors == null )
+	    initializeDamlConstructors(); // FIXME: see above
+	if ( nsuri != null && nsuri.equals(DamlEngine.DAML_NS) )
+	    constructor = damlConstructors.get(node.getLocalName());
+	if ( constructor != null )
+	    try {
+		return constructor.newInstance(new Object[]{node, context, options});
+	    } catch (InstantiationException e) {
+		// FIXME: Do something intelligent here!
+	    } catch (IllegalAccessException e) {
+		// FIXME: Do something intelligent here!
+	    } catch (InvocationTargetException e) {
+		// FIXME: Do something intelligent here!
+	    }
+	return new TodoDefaultElement(node, context, options);
     }
 
 }