@Test
public void testConvert0_With_Prefix() throws Exception {

    Map<String, String> map = converter.convert("pre",
            new SearchUserForm0("yamada", 20));
    assertThat(map.size(), is(2));
    assertThat(map, hasEntry("pre.name", "yamada"));
    assertThat(map, hasEntry("pre.age", "20"));
}