Answers to: Extend Task Json Query

Comment by Flavio Sadeghi on lttung's answer

Flavio Sadeghi — Mon, 22 May 2017 04:10:00 -0400

Hi @lttung, thanks for pointing out the deserialization bug. We will analyze it. Here the link to the issue: https://jira.axonivy.com/jira/browse/XIVY-1923: CaseQuey / TaskQuery json deserialization removes AND-condition when it has only one condition

Answer by lttung

lttung — Thu, 18 May 2017 23:31:08 -0400

Hi Flavio,

The problem is from Json:

TaskQuery orConditions = TaskQuery.create()
  .where().state().isEqual(TaskState.SUSPENDED)
  .or().state().isEqual(TaskState.RESUMED)
  .or().state().isEqual(TaskState.PARKED);

TaskQuery query1 = TaskQuery.create()
  .where().and(orConditions)
  .orderBy().priority();

TaskQuery query2 = TaskQuery.fromJson(query1.asJson()); //The result queries of 1 and 2 are the same.

query1.where().applicationId().isEqual(1); // Correct as expected.
query2.where().applicationId().isEqual(1); // Wrong, the same as Way 1.

Why is query2 the same as query1 before filtering by app but different after that?

Answer by Flavio Sadeghi

Flavio Sadeghi — Thu, 18 May 2017 09:33:34 -0400

The following snipped creates your expected query:

TaskQuery orConditions = TaskQuery.create()
   .where().state().isEqual(TaskState.SUSPENDED)
      .or().state().isEqual(TaskState.RESUMED)
      .or().state().isEqual(TaskState.PARKED);

TaskQuery query = TaskQuery.create()
   .where().and(orConditions)
   .orderBy().priority();

query.where().applicationId().isEqual(1);

Resulting Query:

SELECT *  
  FROM IWA_Task  
  WHERE
  (
      (  Column(IWA_TaskQuery.State) = 4 
      || Column(IWA_TaskQuery.State) = 5 
      || Column(IWA_TaskQuery.State) = 8
      ) 
      && 
      Column(IWA_TaskQuery.ApplicationId) = 1
  ) 
  ORDER BY Column(CurrentPriority) ASCENDING

Way 1: The first 'operator' is a OR-operator. As a result, the root-operator is a or-operator and therefore any further operators are attached to this root-(or-)operator, which results in your written condition.

Way 2: The method and(TaskQuery q) doesn only take the filter (the where-condition) from the passed query.

I would say: the TaskQuery API is a perfect fluent API. When using it to combine multiple condition is is a bit tricky...