java - html umlauts not renderd correctly if progamm executed via jar file -

i have following javacode create html file. use j2html library that:

string html = html(                      head(                          meta().attr("charset", "utf-8"),                          title("test"),                          link().withrel("stylesheet").withhref("style.css")                      ),                      body(                             h1("räte"),                             h2("Äpfel")                      )                    ).render(); file file = new file("index.html"); fileutils.writestringtofile(file, html); 

this works if launch programm via intellij , output:

test

räte

Äpfel

but if create artifact jar , launch it, umlauts aren't displayed correctly. looks this:

test

r�te

�pfel

its same java code , charset set utf-8.