ImmutableSubjectIssuer implements SubjectIssuer { public static SubjectIssuer of(final CharSequence subjectIssuerValue) { checkNotNull(subjectIssuerValue, "subjectIssuerValue"); return new ImmutableSubjectIssuer(subjectIssuerValue.toString()); } private  ImmutableSubjectIssuer(final String subjectIssuer); static SubjectIssuer of(final CharSequence subjectIssuerValue); @Override int length(); @Override char charAt(final int index); @Override CharSequence subSequence(final int start, final int end); @Override boolean equals(final Object o); @Override int hashCode(); @Override @Nonnull String toString();  }
@Test public void createSubjectIssuerWithNullSubjectIssuerValueFails() { assertThatExceptionOfType(NullPointerException.class) .isThrownBy(() -> ImmutableSubjectIssuer.of(null)); }