JDBC - Retrieve Boolean output from Oracle Procedure - stored-procedures

Question

I need to invoke an Oracle procedure with one IN parameter with VARCHAR2 and OUT parameter as BOOLEAN data type.
Below is my code using SimpleJdbcCall
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(getTemplate())
.withCatalogName("package_name")
.withProcedureName("proc_name")
.withoutProcedureColumnMetaDataAccess()
.declareParameters(
new SqlParameter ("userName", Types.VARCHAR),
new SqlOutParameter("status", Types.BOOLEAN)
);
Map<String, Object> inParams = new HashMap<String, Object>();
inParams .put("userName", userInput);
Map<String, Object> outputValue= jdbcCall.execute(inParams);
Exception : CallableStatementCallback; uncategorized SQLException for
SQL [{call PACKAGE_NAME.PROC_NAME(?, ?)}]; SQL state [99999];
error code [17004]; Invalid column type: 16; nested exception is
java.sql.SQLException: Invalid column type: 16
After doing a research i found that "JDBC drivers do not support the passing of Boolean parameters to PL/SQL stored procedures"
It has been suggested to wrap the PL/SQL procedure with a second PL/SQL procedure. The main problem is that i am restricted for write access in the db as that is client data. please help me to fix this issue.
Some of the links i referred
https://docs.oracle.com/cd/F49540_01/DOC/java.815/a64685/tips3.htm
https://community.oracle.com/thread/2139408?tstart=0
https://community.oracle.com/thread/887712?tstart=0
https://community.oracle.com/thread/975159?tstart=0
Stored Function - Sending/Receiving Boolean - BD
http://docs.oracle.com/cd/B28359_01/java.111/b31224/apxtblsh.htm#i1005380

Answer 1

From the official Oracle JDBC documentation:
It is not feasible for Oracle JDBC drivers to support calling
arguments or return values of the PL/SQL RECORD, BOOLEAN, or table
with non-scalar element types. [...] As a workaround to PL/SQL RECORD,
BOOLEAN, or non-scalar table types, create container procedures that
handle the data as types supported by JDBC. For example, to wrap a
stored procedure that uses PL/SQL boolean, create a stored procedure
that takes a character or number from JDBC and passes it to the
original procedure as BOOLEAN or, for an output parameter, accepts a
BOOLEAN argument from the original procedure and passes it as a CHAR
or NUMBER to JDBC. Similarly, to wrap a stored procedure that uses
PL/SQL records, create a stored procedure that handles a record in its
individual components, such as CHAR and NUMBER, or in a structured
object type.
This is exactly what you did in your answer, but I wanted to add the documentation as reference.

Answer 2

I fixed the issue by writing a wrapper procedure to process the result of the actual procedure and sending back the result as varchar data type .
If any of you find it as wrong approach or if you a have any easy way to fix this, please do share your comments.
Below is the procedure:
DECLARE
userName VARCHAR2(13);
status BOOLEAN;
result VARCHAR2(13);
BEGIN
userName := ?;
status := NULL;
package_name.proc_name ( userName, status);
BEGIN
IF status THEN result := 'Yes';
ELSIF NOT status THEN result := 'No';
ELSE result := 'NULL';
END IF;
END;
COMMIT;
? := result;
END ;
Also instead of simpleJdbcCall, i used CallableStatement for processing this. Refer below:
try{
String wrapperProc= "DECLARE userName VARCHAR2(13); status BOOLEAN; result VARCHAR2(13); BEGIN userName := ?; status := NULL; "+
"package_name.proc_name ( userName, status ); BEGIN IF status THEN result := 'Yes'; ELSIF NOT status THEN " +
"result := 'No'; ELSE result := 'NULL'; END IF; END; COMMIT; ? := result;END ;";
CallableStatement proc_stmt= null;
proc_stmt = getTemplate().getDataSource().getConnection().prepareCall(wrapperProc);
proc_stmt.setString(1, "userName");
proc_stmt.registerOutParameter(2, Types.VARCHAR);
proc_stmt.execute();
System.out.println("Final Result : "+proc_stmt.getString(2));
} catch(SQLException e){
System.out.println("SQL Exception : "+e.getMessage());
e.printStackTrace();
} catch (Exception e) {
System.out.println("Exception : "+e.getMessage());
e.printStackTrace();
}
~~Suriya