>"Last time I looked LibreOffice still required Java. "
I can't find a link at this time but I recall the Java dependencies being removed some time back when LO was virtually rewritten somewhere alone the version 4 branch. Some functionality still requires a Java machine but Java is DISABLED by default in most rendering.. experience may vary if using Linux, I believe.
Don't do Windows so can't run up LO for Windows to check on that.
I have found a link on the current status of Java dependency in LO and it seems very little: