### Question:
CalculationTasks implements ImmutableBean { @Override public String toString() { return Messages.format("CalculationTasks[grid={}x{}]", targets.size(), columns.size()); } private  CalculationTasks(List<CalculationTask> tasks, List<Column> columns); private  CalculationTasks(
      List<CalculationTarget> targets,
      List<Column> columns,
      List<CalculationTask> tasks); static CalculationTasks of(
      CalculationRules rules,
      List<? extends CalculationTarget> targets,
      List<Column> columns); static CalculationTasks of(
      CalculationRules rules,
      List<? extends CalculationTarget> targets,
      List<Column> columns,
      ReferenceData refData); static CalculationTasks of(List<CalculationTask> tasks, List<Column> columns); MarketDataRequirements requirements(ReferenceData refData); @Override String toString(); static TypedMetaBean<CalculationTasks> meta(); @Override TypedMetaBean<CalculationTasks> metaBean(); List<CalculationTarget> getTargets(); List<Column> getColumns(); List<CalculationTask> getTasks(); @Override boolean equals(Object obj); @Override int hashCode();  }### Answer:
@Test public void testToString() { List<TestTarget> targets = ImmutableList.of(TARGET1, TARGET1); List<Column> columns = ImmutableList.of( Column.of(TestingMeasures.PRESENT_VALUE), Column.of(TestingMeasures.PRESENT_VALUE), Column.of(TestingMeasures.PRESENT_VALUE)); CalculationRules rules = CalculationRules.of(CALC_FUNCTIONS, USD); CalculationTasks task = CalculationTasks.of(rules, targets, columns); assertThat(task.toString()).isEqualTo("CalculationTasks[grid=2x3]"); }