Use factories implemented as nested classes (rather than reflected constructors) to store classes to instantiate.

Now every subclass of TodoElement or TodoAttr should also come with a
nested subclass of TodoElement.Factory or TodoAttr.Factory which just
contains a(n instance) method to call its constructor.  In essecne,
the factory instance is just used as a pointer to the class to create
(or its constructor, as in the previous version).

1 files changed, 15 insertions, 17 deletions

diff --git a/org/madore/damlengine/TodoElement.java b/org/madore/damlengine/TodoElement.java
index a069b36..e2293ef 100644
--- a/org/madore/damlengine/TodoElement.java
+++ b/org/madore/damlengine/TodoElement.java
@@ -1,17 +1,23 @@
 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 abstract class TodoElement extends TodoItem {
 
-    protected static Map<String,Constructor<? extends TodoElement>> damlConstructors;
+    public static abstract class Factory {
+	public abstract TodoElement newItem(Element node,
+					    Map<String,Object> context,
+					    Map<String,Object> options);
+    }
+
+    protected static Map<String,Factory> damlFactories;
+    protected static Factory damlDefaultFactory;
 
     static {
-	damlConstructors = new HashMap<String,Constructor<? extends TodoElement>>();
+	damlFactories = new HashMap<String,Factory>();
+	damlDefaultFactory = new TodoDefaultElement.Factory();
     }
 
     Element node;
@@ -27,21 +33,13 @@ public abstract class TodoElement extends TodoItem {
     public static TodoElement getTodoElement(Element node,
 					     Map<String,Object> context,
 					     Map<String,Object> options) {
-	Constructor<? extends TodoElement> constructor = null;
+	Factory factory = null;
 	String nsuri = node.getNamespaceURI();
 	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);
+	    factory = damlFactories.get(node.getLocalName());
+	if ( factory == null )
+	    factory = damlDefaultFactory;
+	return factory.newItem(node, context, options);
     }
 
 }