docs: private void readObject(ObjectInputStream in) throws ClassNotFoundException, IOException {
          final boolean trace = TraceComponent.isAnyTracingEnabled();
          if (trace && tc.isEntryEnabled())
              Tr.entry(this, tc, "readObject");
  
          GetField fields = in.readFields();
  
          readState(fields);
  
          subjectManager = new SubjectManager();
  
          if (trace && tc.isEntryEnabled()) {
              Tr.exit(this, tc, "readObject",
                      new Object[] { "deserialized caller/invocation principals: ", callerPrincipal, invocationPrincipal,
                                    "subjects are equal? ", subjectsAreEqual, "jaasLoginContextEntry: ", jaasLoginContextEntry });
          }
      }