Signing Jar Files

From LWJGL
Jump to: navigation, search

To run LWJGL applets, you need to sign all your jar files, including the lwjgl_util_applet.jar, lwjgl.jar, and all the natives JAR files.

To do this, you need to create a key. A key is what you will be signing all your jars with. Remember you only need to create a key once, then you can use as many times as you want.


You must have the JDK's bin folder in the path

Type "keytool" into the command prompt. If you get an error saying it can't find that command, then you need to Google how to add a folder to the PATH on your operating system, as the procedure varies between Windows, Linux, and Mac.


To create a key, type the following command on the command line:

keytool -genkeypair -alias <alias>

The alias is the name of the key you want to create.

After typing the keytool command, it is going to ask you a couple questions:

  • password for the keystore
  • your full name
  • your organisational unit name
  • your organisation name
  • your city
  • your state
  • your two-letter country code (like for the United States is US)
  • confirmation that all info is correct
  • password for that alias, you may choose to use the same password as the keystore by pressing enter or use a different password


After creating a key, you can sign all your jars with this command:

jarsigner <path to jar> <alias>

After typing the jarsigner command, it is going to ask you:

  • password for the keystore
  • password for the alias (only if you set it to a different one)