Set the default constructor on config classes private.

- Default constructors for arrays are still public.

1 files changed, 7 insertions, 3 deletions

diff --git a/config-lib/src/main/java/com/yahoo/config/InnerNodeVector.java b/config-lib/src/main/java/com/yahoo/config/InnerNodeVector.java
index 72ca0138a53..eec2d3cd500 100644
--- a/config-lib/src/main/java/com/yahoo/config/InnerNodeVector.java
+++ b/config-lib/src/main/java/com/yahoo/config/InnerNodeVector.java
@@ -1,6 +1,8 @@
 // Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.config;
 
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
 import java.util.List;
 
 /**
@@ -38,9 +40,11 @@ public class InnerNodeVector<NODE extends InnerNode> extends NodeVector<NODE> {
     @SuppressWarnings("unchecked")
     protected NODE createNew() {
         try {
-            return (NODE) defaultNode.getClass().newInstance();
-        } catch (IllegalAccessException | InstantiationException ex) {
-            throw new ConfigurationRuntimeException(ex);
+            Constructor<? extends InnerNode> ctor  = defaultNode.getClass().getDeclaredConstructor();
+            ctor.setAccessible(true);
+            return (NODE) ctor.newInstance();
+        } catch (InvocationTargetException | IllegalAccessException | InstantiationException | NoSuchMethodException e) {
+            throw new ConfigurationRuntimeException(e);
         }
     }