I want to know if Netbeans has some option or setting that will allow me to automatically sign a jar as part of the build.
You could use the maven plugin for that. Netbeans is able to open and create maven files out-of-the-box.
If you need signing for jnlp you could look into this and that explanation, which works fine in my TimeFinder project see the pom.xml.
In your -post-jar
ant target, it may be convenient to read the <signjar> password from a file, e.g. ~/.keyconf. Give the file user-only access: e.g. 400
or 600
.
<loadfile srcfile="${user.home}/.keyconf" property="keyconf"/>
<signjar alias="..." storepass="${keyconf}">
...
</signjar>