public void setMeta(String key, String value)
    {
        metadata.set(key, value);
    }
@Test
    public void testSetMeta()
    {
        ZCert cert = new ZCert();

        cert.setMeta("version", "1");
        String version = cert.getMeta("version");
        assertThat(version, is("1"));

        cert.setMeta("version", "2");
        version = cert.getMeta("version");
        assertThat(version, is("2"));
    }