How to reproduce:

• Set an empty long data in the repository
• Get this data with a default value via the new API (dataHolder.getValue(dataPath,  defaultValue))
• The retrieved value is the default one => OK
• Set an empty string data in the repository
• Get this data with a default value via the new API
• The retrieved value is empty => KO

With the old API (compositeMetadata.getString(dataPath, defaultValue)), the retrieved value was empty too. But the empty notion did not exist for other types.

Look for all calls of the old or new API that really use the default value to choose the behavior of this method