Question

Problem: Report Templates are created by Admin Users who only decide what data to show where as the filter for the data is specified by the business user. In simpler SQL terms, query is specified by the Admin User, Business User specifies the WHERE clause.

Jasper allows user to specify parameters in SQL query like $P{city}. I have tried to retrieve the query dynamically using the method specfied in the link.

Possible Solution can be

1. Use WHERE clause parameters in JRXML and replace them while report creation – This will save me SQL parsing but I don’t want to guide the admin user with this complexity. Parsing is not a huge problem.
2. Use my custom jdbc query executor and factory, only created to allow me extension point before jasper fire SQL query. I will be completely relying on vanilla Jasper JDBC data source but will only modify query before execution. JRAbstractQueryExecuter simplifies the query and replace the jasper related tokens before firing query – This will be very dirty and will force me to be implementation specific.
3. Do the same replacement as it is done in JRAbstractQueryExecuter in my application code base, parse the SQL query, modify it and set it again as specified in link

Can you please suggest a better way of doing this? I have a feeling that this can definitly be done in cleaner way.

Thanks for your help

Answer 1

You could create an input control to determine the desired WHERE clause and use a parameter to hold the contents of that WHERE clause. The default value expression would be something like:

 $P{theParameter} == "value_1" ?
     (" AND CONDITION_1 IN ('A', 'B', 'C') AND CONDITION_2 = 'Yes' "
     ) : " AND CONDITION_3 = 'Other' AND CONDITION_4 = 'No' "

Then in your WHERE clause you would reference it like:

 WHERE
      .... = .....
      AND .... = ....
      AND .... = ....
      $P!{theParameter}

If your constraint columns are the same across your WHERE clauses, you could use $P! to bring in the parameter value literally, and reference it in your query:

 WHERE
      .... = .....
      AND .... = ....
      AND .... = ....
      AND thisValue = $P!{theParameter}