Iterator says we need to do the work in next()

and add remove() method for Java1.7 compat

h2/src/main/org/h2/util/ValueHashMap.java

@@ -204,24 +204,27 @@ public class ValueHashMap<V> extends HashBase {
     }
 
     private final class EntryIterator implements Iterator<Map.Entry<Value, V>> {
-        int keysIndex = -1;
+        private int keysIndex = -1;
+        private int left = size;
 
         @Override
         public boolean hasNext() {
-            if (keysIndex >= keys.length)
-                return false;
+            return left > 0;
+        }
+
+        @Override
+        public Map.Entry<Value, V> next() {
+            left--;
             do {
                 keysIndex++;
-                if (keysIndex >= keys.length)
-                    return false;
                 if (keys[keysIndex] != null && keys[keysIndex] != ValueNull.DELETED)
-                    return true;
+                    return new DataUtils.MapEntry<Value, V>(keys[keysIndex], values[keysIndex]);
             } while (true);
         }
-
+        
         @Override
-        public Map.Entry<Value, V> next() {
-            return new DataUtils.MapEntry<Value, V>(keys[keysIndex], values[keysIndex]);
+        public void remove() {
+            throw new UnsupportedOperationException();
         }
     }