What is the jarsigner tool?

The next tool we'll look at is the jarsigner tool; this tool creates signed JAR files. The jarsigner tool uses the information in a keystore to look up information about a particular entity and uses that information either to sign or to verify a JAR file. 

The keystore that jarsigner uses is subject to the KeyStore class that has been installed into the virtual machine; if you have your own keystore implementation, jarsigner will be able to use it. Similarly, if you use the standard keystore implementation, but hold the keys in a file other than the default .keystorefile, jarsigner will allow you to use that other file as well.

Here are some of the screenshots:

 https://docstore.mik.ua/orelly/java-ent/security/appa_02.htm