JEX is a Java-based XML editing software that offers easy hierarchy manipulation. It is free, open-source and licensed under Public Domain terms.
The interface is user-friendly, meaning you don't need to have any prior experience to use the software. With its convenient editing tool, you can easily edit an XML file without any hassle. JEX also allows users to perform a series of operations to manipulate the hierarchy of the XML, making it more conducive for users.
Finally, it's worth mentioning that JEX is licensed and distributed under the Public Domain License terms, giving users the freedom to modify, distribute, or use the program as they please. So if you're looking for a competent, free and open-source Java XML editor, JEX is the ideal software to get started with.