String s = ctx.toString();
        assertEquals("KERB5[src=client,targ=service,mech=1.2.3]", s);
    }

    @Test
    @DisplayName("toString falls back when GSS access fails")
    void toString_established_throws() throws Exception {
        when(gssContext.isEstablished()).thenReturn(true);
        when(gssContext.getSrcName()).thenThrow(new GSSException(GSSException.FAILURE));
        String s = ctx.toString();