How to merge two java.util.Properties objects?

Question

I\'m trying to have a default java.util.Properties object in my class, with the default properties it accepts, and let the developer override some of them by sp

Answer 1

putAll(): Copies all of the mappings from the specified map to this hashtable. These mappings will replace any mappings that this hashtable had for any of the keys currently in the specified map.

Properties merged = new Properties();
merged.putAll(properties1);
merged.putAll(properties2);

Line 2 has no effect at all. None of the properties from the first file will be in the merged properties object.