Selective combination of querys

[lestat86]

Hi everyone.

i'm building a specific filter mechanism in my gui, that allows the user to select only some subset of processes based on a few different attributes (like start date, the value of certain process variables, and so on).
Being a filter, every filtering field can be present or not.
That said, i'm trying to find a way of combining pre made queries, like the following:

ProcessInstanceQuery q1 = getProcessInstance().createProcessInstanceQuery()… .involvedUser(user1);

ProcessInstanceQuery q1 = getProcessInstance().createProcessInstanceQuery()… .variableValueLike(var, value);

…
…

FinalQuery = q1 or q1 or … .listPage(start, number).

How can i implement the last part, i.e. the combining part?

Thanks a lot!

[jbarrez]

Currently we have only limited support for or queries. So we've got nothing out of the box sadly that would cover that. Maybe a custom query is the answer here?

[lestat86]

Hi and thanks for the reply.

Custom query might be the answer but it would be a rather complicated one… I've tried using null references and regular expressions but it doesn't work the way i expect.
Keep in mind that the user is using this filter in a multichoice way, meaning that he can select multiple value for multiple process variables and this can potentially generate null pointers like crazy (in my experience).

One way i thought it might be possible is to create a native query using string composition, but i've no idea how to print the sql of a custom generated query so i have no idea on how to modify the code…

[jbarrez]

Hmm so what about a custom Mybatis query: http://www.jorambarrez.be/blog/2014/01/17/execute-custom-sql-in-activiti/

Do note that I noticed that in the latest version the annotation approach seems to be bugged , the old-school XML counterpart does work.

[echashnik]

Did use direct connection to DB and it's work. Not sure that it's correct approach thou:
…
private static ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
private static RuntimeService runtimeService = processEngine.getRuntimeService();
…
private static String getEndPointByName(String name) throws SQLException {
  final String selEp = "SELECT PROTOCOL, HOST, PORT, PATHURI FROM ENDPOINT_CONFIGURATION WHERE NAME='" + name + "';";
  String ep = "";
  ProcessEngineConfiguration processEngineConfiguration = processEngine.getProcessEngineConfiguration();
  DataSource dataSource = processEngineConfiguration.getDataSource();
  Connection connection = dataSource.getConnection();
  PreparedStatement preparedStatement = connection.prepareStatement(selEp);
  ResultSet rs = preparedStatement.executeQuery();
  while (rs.next()) {
   String pt=rs.getString("PROTOCOL");
   String host = rs.getString("HOST");
   String port = rs.getString("PORT");
   String uri = rs.getString("PATHURI");
   ep="https://";
   if(pt.equals("0")){
    ep="http://";
   }
   ep += host;
   if (port != null) {
    ep += ":" + port;
   }
   ep += uri;
  }
  rs.close();
  preparedStatement.close();
  connection.close();
  return ep;
}

[jbarrez]

Not sure what you're trying to do here? Is this in the Alfresco BPM Suite?
If so, it's way easier of adding a custom Spring bean and injecting the corresponding Repository class to get db data.