### Question:
JdbcDatabaseConfig { @Config("metadata.db.url") public JdbcDatabaseConfig setUrl(String url) { this.url = url; return this; }  @NotNull String getUrl(); @Config("metadata.db.url") JdbcDatabaseConfig setUrl(String url);  }### Answer:
@Test public void testDefaults() { assertRecordedDefaults(recordDefaults(JdbcDatabaseConfig.class) .setUrl(null)); }
@Test public void testExplicitPropertyMappings() { Map<String, String> properties = ImmutableMap.<String, String>builder() .put("metadata.db.url", "jdbc:test: .build(); JdbcDatabaseConfig expected = new JdbcDatabaseConfig() .setUrl("jdbc:test: assertFullMapping(properties, expected); }