Do not use BASE64Encoder/Decoder APIs from the sun.* packages

The sun.misc.BASE64Encoder and sun.misc.BASE64Decoder have been removed in Java SE 11. Instead, use the supported java.util.Base64 class, which was added in Java SE 8.

This rule has an automated fix. The fix changes sun.misc.Base64Encoder/Decoder to java.util.Base64.getEncoder()/getDecoder() by default and switches to java.util.Base64.getMimeEncoder()/getMimeDecoder()if required. Copy the custom configuration to your application build file to enable the fix automation.

For more information, see the Class Base64 documentation.