archaius-core/src/main/java/com/netflix/config/ConcurrentMapConfiguration.java
@Override
    public void copy(Configuration c)
    {
        if (c != null)
        {
            for (Iterator it = c.getKeys(); it.hasNext();)
            {
                String key = (String) it.next();
                Object value = c.getProperty(key);
                if (key != null && value != null) {
                    setProperty(key, value);
                }
            }
        }
    }
@Override
    public void copy(Configuration c)
    {
        if (c != null)
        {
            for (Iterator it = c.getKeys(); it.hasNext();)
            {
                String key = (String) it.next();
                Object value = c.getProperty(key);
                if (key != null && value != null) {
                    setProperty(key, value);
                }
            }
        }
    }
Copy properties of a configuration into this configuration. This method simply
iterates the keys of the configuration to be copied and call {@link #setProperty(String, Object)}
for non-null key/value.