title: Jarsigner is not recognized internal or external command
body: <p>i'm trying to check if my signed release apk is really signed.
  But following some tutorials, or the single i've found .</p>
  
  <pre><code>$ jarsigner -verify -verbose -certs my_application.apk
  </code></pre>
  
  <p>I am receiving this message : "Jarsigner is not recognized internal external command".</p>
  
  <p>Remembering that my apk is in the same folder of jarsigner.exe
  I dont know what to do. </p>