How to fetch cascading SQL from WEBI reports 3.1?

I tried to get the Cascading Query from WebI reports version 3.1 (see the below code for reference) but this code is not fetching all queries.

SQLDataProvider sqldp;

SQLContainer sqlcntr = null;

int containerCnt = 0;

SQLNode sqlnode =  null;

SQLSelectStatement SqlSel = null;

String sqlStatement = null;

if (dp instanceof SQLDataProvider)

{

  sqldp = (SQLDataProvider) dp;

  if (sqldp.isCustomSQL())

  {

   sqlcntr = sqldp.getSQLContainer();

// sqlcntr = sqldp.getSQLContainer(false);

  if (sqlcntr != null )

    {

  //containerCnt = sqlcntr.getChildCount();

  sqlnode =  (SQLNode) sqlcntr.getChildAt(0);

  SqlSel = (SQLSelectStatement) sqlnode;            

  sqlStatement = SqlSel.getSQL();

  }

  }

}

I also tried with "getSQLContainer(false)" but it fails to provide DataProvider. Suggest any way to get the Cascading queries.