Output SYS_REFCURSOR when cursor structure is not known

Question

If i have a variable of type "SYS_REFCURSOR".
This cursor will be passed to various procedures which open various recordset for that cursor, with various number of columns in cursor.
How to output cursor all columns?
1. Maybe java will have metadata information for cursor and can output the resultset of cursor. If so, then this is ok to choose this solution. also VbScript is ok, if it can help.
2. Maybe one can create table temporarily based on the cursor. And table objects have meta data in oracle system tables, so i can output all cursor data.
3. Maybe i can use so called try-catch clauses techique to help somehow. For example
Try
  fetch cur1 into varchar2_var1, .., varchar2_var5
catch (if error)
      try
          fetch cur1 into varchar2_var1, .., varchar2_var4
Till we know how many fields there are.
somehow this way to go next4. Maybe execute immediate can help somehow.

Answer 1

If you're not in 11g and you at least have some options of structures you want to try and fetch to, you can make use of the rowtype_mismatch exception by catching it and trying to fetch into a different structure until you find it, by nesting PL/SQL begin...exception...end; blocks.
You won't lose rows if you attempt to fetch into the wrong structure.
In the example below I try to fetch into a type with 2 columns and it fails then I attempt again against a 3-column type.
Note that the column type mismatch on implicit conversions will throw other exceptions as ORA-06504 or ORA-01722 for example.
Connected to Oracle Database 10g Enterprise Edition Release 10.2.0.4.0
Connected as fsitja
SQL> set serveroutput on
SQL>
SQL> DECLARE
  2    cur SYS_REFCURSOR;
  3    TYPE t_rec1 IS RECORD(
  4      col1 NUMBER,
  5      col2 VARCHAR2(100));
  6    v_rec1 t_rec1;
  7    TYPE t_rec2 IS RECORD(
  8      col3 NUMBER,
  9      col4 VARCHAR2(100),
10      col5 VARCHAR2(100));
11    v_rec2 t_rec2;
12  BEGIN
13    OPEN cur FOR
14      SELECT 1 col3, 'a' col4, 'b' col5 FROM dual;
15    FETCH cur
16      INTO v_rec1;
17    dbms_output.put_line('REC1.COL1: ' || v_rec1.col1);
18    dbms_output.put_line('REC1.COL2: ' || v_rec1.col2);
19  EXCEPTION
20    WHEN rowtype_mismatch THEN
21      FETCH cur
22        INTO v_rec2;
23      dbms_output.put_line('REC2.COL3: ' || v_rec2.col3);
24      dbms_output.put_line('REC2.COL4: ' || v_rec2.col4);
25      dbms_output.put_line('REC2.COL5: ' || v_rec2.col5);
26  END;
27  /
REC2.COL3: 1
REC2.COL4: a
REC2.COL5: b
PL/SQL procedure successfully completed
SQL>