### Question:
UpsertConfig extends BaseJsonConfig { @JsonCreator public UpsertConfig(@JsonProperty(value = "mode") Mode mode) { Preconditions.checkArgument(mode != Mode.PARTIAL, "Partial upsert mode is not supported"); _mode = mode; } @JsonCreator  UpsertConfig(@JsonProperty(value = "mode") Mode mode); @JsonProperty(MODE_KEY) Mode getMode(); static final String MODE_KEY; }### Answer:
@Test public void testUpsertConfig() { UpsertConfig upsertConfig = new UpsertConfig(UpsertConfig.Mode.FULL); assertEquals(upsertConfig.getMode(), UpsertConfig.Mode.FULL); try { new UpsertConfig(UpsertConfig.Mode.PARTIAL); fail(); } catch (IllegalArgumentException e) { } }