diff -r c7841bbe1227 -r 7ae6c0fd479b test/tools/javac/multicatch/model/ModelChecker.java
--- a/test/tools/javac/multicatch/model/ModelChecker.java	Thu Apr 28 08:46:06 2011 -0700
+++ b/test/tools/javac/multicatch/model/ModelChecker.java	Thu Apr 28 15:05:36 2011 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2010, 2011 Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -30,7 +30,7 @@
  * @compile -processor ModelChecker Model01.java
  */
 
-import com.sun.source.tree.VariableTree;
+import com.sun.source.tree.CatchTree;
 import com.sun.source.util.TreePathScanner;
 import com.sun.source.util.Trees;
 import com.sun.source.util.TreePath;
@@ -41,6 +41,12 @@
 import javax.lang.model.element.Element;
 import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.TypeMirror;
+import javax.lang.model.type.TypeKind;
+import javax.lang.model.type.UnionType;
+import javax.lang.model.type.UnknownTypeException;
+import javax.lang.model.util.SimpleTypeVisitor6;
+import javax.lang.model.util.SimpleTypeVisitor7;
 
 @SupportedAnnotationTypes("Check")
 public class ModelChecker extends JavacTestingAbstractProcessor {
@@ -69,22 +75,61 @@
         }
 
         @Override
-        public Void visitVariable(VariableTree node, Void p) {
-            Element ex = trees.getElement(getCurrentPath());
+        public Void visitCatch(CatchTree node, Void p) {
+            TreePath param = new TreePath(getCurrentPath(), node.getParameter());
+            Element ex = trees.getElement(param);
+            validateUnionTypeInfo(ex);
             if (ex.getSimpleName().contentEquals("ex")) {
                 assertTrue(ex.getKind() == ElementKind.EXCEPTION_PARAMETER, "Expected EXCEPTION_PARAMETER - found " + ex.getKind());
-                for (Element e : types.asElement(ex.asType()).getEnclosedElements()) {
+                for (Element e : types.asElement(trees.getLub(node)).getEnclosedElements()) {
                     Member m = e.getAnnotation(Member.class);
                     if (m != null) {
                         assertTrue(e.getKind() == m.value(), "Expected " + m.value() + " - found " + e.getKind());
                     }
                 }
-                assertTrue(assertionCount == 3, "Expected 3 assertions - found " + assertionCount);
+                assertTrue(assertionCount == 9, "Expected 9 assertions - found " + assertionCount);
             }
-            return super.visitVariable(node, p);
+            return super.visitCatch(node, p);
         }
     }
 
+    private void validateUnionTypeInfo(Element ex) {
+        UnionTypeInfo ut = ex.getAnnotation(UnionTypeInfo.class);
+        assertTrue(ut != null, "UnionType annotation must be present");
+
+        TypeMirror expectedUnionType = ex.asType();
+        assertTrue(expectedUnionType.getKind() == TypeKind.UNION, "UNION kind expected");
+
+        try {
+            new SimpleTypeVisitor6<Void, Void>(){}.visit(expectedUnionType);
+            throw new RuntimeException("Expected UnknownTypeException not thrown.");
+        } catch (UnknownTypeException ute) {
+            ; // Expected
+        }
+
+        UnionType unionType = new SimpleTypeVisitor7<UnionType, Void>(){
+            @Override
+            protected UnionType defaultAction(TypeMirror e, Void p) {return null;}
+
+            @Override
+            public UnionType visitUnion(UnionType t, Void p) {return t;}
+        }.visit(expectedUnionType);
+        assertTrue(unionType != null, "Must get a non-null union type.");
+
+        assertTrue(ut.value().length == unionType.getAlternatives().size(), "Cardinalities do not match");
+
+        String[] typeNames = ut.value();
+        for(int i = 0; i < typeNames.length; i++) {
+            TypeMirror typeFromAnnotation = nameToType(typeNames[i]);
+            assertTrue(types.isSameType(typeFromAnnotation, unionType.getAlternatives().get(i)),
+                       "Types were not equal.");
+        }
+    }
+
+    private TypeMirror nameToType(String name) {
+        return elements.getTypeElement(name).asType();
+    }
+
     private static void assertTrue(boolean cond, String msg) {
         assertionCount++;
         if (!cond)