### Question:
Grid implements Serializable { @Override public String toString() { return GoodDataToStringBuilder.defaultToString(this); } @JsonCreator  Grid(@JsonProperty("columns") @JsonDeserialize(contentUsing = GridElementDeserializer.class)
                        List<? extends GridElement> columns,
                @JsonProperty("rows")  @JsonDeserialize(contentUsing = GridElementDeserializer.class)
                        List<? extends GridElement> rows,
                @JsonProperty("metrics") List<MetricElement> metrics,
                @JsonProperty("sort") Map<String, List<String>> sort,
                @JsonProperty("columnWidths") Collection<Map<String, Object>> columnWidths);  Grid(List<? extends GridElement> columns, List<? extends GridElement> rows, List<MetricElement> metrics); @JsonSerialize(contentUsing = GridElementSerializer.class) List<? extends GridElement> getColumns(); @JsonSerialize(contentUsing = GridElementSerializer.class) List<? extends GridElement> getRows(); List<MetricElement> getMetrics(); Collection<Map<String, Object>> getColumnWidths(); Map<String, List<String>> getSort(); @Override String toString();  }### Answer:
@Test public void testToStringFormat() throws Exception { final Grid grid = readObjectFromResource("/md/report/grid.json", Grid.class); assertThat(grid.toString(), matchesPattern(Grid.class.getSimpleName() + "\\[.*\\]")); }