src/java.base/share/classes/javax/net/ssl/SSLProtocolException.java

@@ -34,10 +34,11 @@
  * @author David Brownell
  */
 public
 class SSLProtocolException extends SSLException
 {
+    @java.io.Serial
     private static final long serialVersionUID = 5445067063799134928L;
 
     /**
      * Constructs an exception reporting an SSL protocol error
      * detected by an SSL subsystem.