utl_file.INVALID_OPERATION error

Hi, Experts,

I have a PROCEDURE to open a flat file.  The following is code;

 v_check_FHandle        UTL_FILE.FILE_TYPE;
  v_input_dir            varchar2(100) :='DEPWORK';
  v_input_file            varchar2(100);
  v_check_stmt               VARCHAR2(2000);
  v_check_cnt           number:=0;
  v_check_flag          boolean := TRUE;

      ---------------------------------------------
      -- Checking the Existance of the file
      ---------------------------------------------
begin
      BEGIN
      v_input_file := 'test_data.out';
          v_check_FHandle := utl_file.fopen(v_input_dir,v_input_file,'R');
          utl_file.get_line(v_check_FHandle, v_check_stmt);
          v_check_cnt := v_check_cnt + 1;
          utl_file.fclose(v_check_Fhandle);
          IF v_check_cnt > 0 then
            v_check_flag := FALSE;
          END IF;
        EXCEPTION
          When NO_DATA_FOUND then
          -- the file exists, but has zero bytes
          utl_file.fclose(v_check_Fhandle);
            v_check_flag := TRUE;
  WHEN utl_file.invalid_mode THEN
    RAISE_APPLICATION_ERROR (-20051, 'Invalid Mode Parameter');
  WHEN utl_file.invalid_path THEN
    RAISE_APPLICATION_ERROR (-20052, 'Invalid File Location');
  WHEN utl_file.invalid_filehandle THEN
    RAISE_APPLICATION_ERROR (-20053, 'Invalid Filehandle');
  WHEN utl_file.invalid_operation THEN
    RAISE_APPLICATION_ERROR (-20054, 'Invalid Operation');
  WHEN utl_file.read_error THEN
    RAISE_APPLICATION_ERROR (-20055, 'Read Error');
  WHEN utl_file.internal_error THEN
    RAISE_APPLICATION_ERROR (-20057, 'Internal Error');
  WHEN utl_file.charsetmismatch THEN
    RAISE_APPLICATION_ERROR (-20058, 'Opened With FOPEN_NCHAR
    But Later I/O Inconsistent');
 WHEN utl_file.file_open THEN
    RAISE_APPLICATION_ERROR (-20059, 'File Already Opened');
 WHEN utl_file.invalid_maxlinesize THEN
    RAISE_APPLICATION_ERROR(-20060,'Line Size Exceeds 32K');
 WHEN utl_file.invalid_filename THEN
    RAISE_APPLICATION_ERROR (-20061, 'Invalid File Name');
 WHEN utl_file.access_denied THEN
    RAISE_APPLICATION_ERROR (-20062, 'File Access Denied By');
 WHEN utl_file.invalid_offset THEN
    RAISE_APPLICATION_ERROR (-20063,'FSEEK Param Less Than 0');
 WHEN others THEN
    RAISE_APPLICATION_ERROR (-20099, 'Unknown UTL_FILE Error');
     end;
    BEGIN
   -- Open the input file for reading
   if v_check_flag then
   v_check_FHandle:=UTL_FILE.FOPEN(v_input_dir,v_input_file,'R');
   end if;
   DBMS_OUTPUT.PUT_LINE('File Opened for read.');
    end;
end;

When I run this in sqlplus, I got a error:
PLS-00483: exception 'INVALID_OPERATION' may appear in at most one exception handler in this block

Please help.  Thanks!