Eclipse BIRT : how to set a parameter as list ?

Need to pass a list as parameter to report ? The answer is this can't be done with current BIRT 4.5.0 implementation , but we  have alternatives :

Why it can't be done ?

When creating a "New Parameter" , there is no such "Data Type" as "List" 

What is the use case ?

oid	username
1	Jeff
2	Tom
3	William

Suppose we have a "String" type parameter : paramoid , and JDBC datasource with below query :

select oid as "ID" , username as "NAME"

from table_user

where oid in (?)

When we pass in "2,3" from application to report as paramoid , the report engine would get data with below SQL query which is obviously wrong  :

select oid as "ID" , username as "NAME"

from table_user

where oid in ('2,3')

Solution : use data set pre open

Rewrite SQL to below :

select oid as "ID" , username as "NAME"

from table_user

where ##oid_condition##

Click on the dataset that being used and put below code to "Before open" :

var oidSelected=reportContext.getParameterValue("paramoid");  

this.queryText = this.queryText.replace("##oid_condition##" , " oid in ("+ oidSelected +")");

In the end , at runtime the SQL become :

select oid as "ID" , username as "NAME"

from table_user

where oid in (2,3)