### Question:
Stock { @Override public String toString() { return symbol + " at " + date + " = " + value; } @JsonCreator  Stock(
      @NonNull @JsonProperty("symbol") String symbol,
      @NonNull @JsonProperty("date") Instant date,
      @NonNull @JsonProperty("value") BigDecimal value); @NonNull String getSymbol(); @NonNull Instant getDate(); @NonNull BigDecimal getValue(); @Override boolean equals(Object o); @Override int hashCode(); @Override String toString();  }### Answer:
@Test void should_return_formatted_stock_value() { var i = Instant.parse("2019-01-01T12:34:56.789Z"); BigDecimal value = BigDecimal.valueOf(42); var stock = new Stock("ABC", i, value); var actual = stock.toString(); assertThat(actual).isEqualTo("ABC at " + i + " = " + value); }