---

CdbBdbLoadList.hh

Go to the documentation of this file.

#ifndef CDBBDB_LOADLIST_HH
#define CDBBDB_LOADLIST_HH

// File and Version Information:
//      $Id: CdbBdbLoadList.hh,v 1.3 2002/09/23 22:39:08 gapon Exp $

#include "BdbCond/BdbObject.hh"
#include "BdbCond/BdbCondProxyBase.hh"

#include <string>

/// Multiple objects loader
/**
 // Description: CdbBdbLoadList. is a utility class intended to be used to
 // simplify loading multiple objects in the conditions database.  It pulls together
 // code for manipulating date-time strings in one place, avoiding code duplication
 // and hopefully simplifying user code.  Unfortunately, the task of loading conditions
 // data is somewhat complicated, so this class is not trivial to use; please read the
 // following instructions carefully!!
 //
 // File format:
 //   CdbBdbLoadList will load a set of objects into a specified container in the
 //   conditions database.  The list of 'objects' is passed to the constructor of this class
 //   in the form of a filename, where each line in the file specifies an 'object'.
 //   The filename must be fully specified: we recommend use AbsParmFilename, and passing
 //  the value of the 'pathname()' function.
 //   The format of the lines in this file is fixed, according to the following perscription:
 //
 //   'RWDate string' ['RWTime string'] ['object specification']
 //
 //   Valid RWDate string formats are described in the Tools.h++ handbook, and include
 //   the BaBar standard '01Jan1901' (ddMmmyyyy).  Valid RWTime strings are similairly
 //   described in the manual and include the BaBar standard '00:00:01' (hh:mm:ss).
 //   Valid 'object specification' format is defined by user code, as described below.
 //   The object list file may have as many lines of the format above as required to
 //   define the desired timeline in the conditions database.  The date/times must be
 //   in ascending order.  The time specified on the line is interpreted as the objects
 //   start-validity time, and the time specified on the _following_ line is interpreted
 //   as the end-validity time of this object.  If there is no new object with start-validity
 //   of this 2nd time (IE if you wish to insert 'gaps' into the conditions timeline), simply
 //   leave the 'object specification' string blank.  The last line in every file must _always_
 //   have a null object specification, to correctly terminate the validity timeline.
 //   For instance, to allow the last object specified to have
 //   indefinite validity, the last line in the file should be simply "+Infinity".  'Dates'
 //   of +Infinity do not need to have a corresponding time, and no object is allowed to have
 //   start-validity of +Infinity.
 //
 //   Comments can be inserted anywhere in the object specfication file by starting the line with
 //   the "#" character.  mid-line comments are not supported.
 //
 //   The times specified in the file are by default assumed to be in UTC.  If instead the
 //   times correspond to the local time zone (the one in which the program is being run),
 //   the following line will change the default:
 //
 //   Zone Local
 //
 //   Please note that the local time zone should only be used if the objects correspond to
 //   actual measurments made at the specified time; it should _never_ be used to describe
 //   simulation parameters for instance.
 //
 // Object specification
 //   CdbBdbLoadList does not understand how to create an instance of your object.
 //   Instead, it defers to a function provided by the user on construction to convert
 //   the 'object specification' string to an object.  One simple way of doing this is
 //   to put the data members for each object in their own file, and have the 'object
 //   specification' represent the name of that file.  Other strategies may be implemented
 //   as appropriate.  CdbBdbLoadList does not need to know the type (class) of the object
 //   being loaded, as it uses persistent polymorphism.
 //   On construction, the user must provide a function of the following prototype:
 //   void createObject(const RWCString& object_specification,
 //                     BdbRefAny& clusterhint,
 //                     BdbRef(BdbObject)& objecthandle);
 //   This function should interpret the object specification as required, 
 //   and construct a persistent object of the correct type, clustered at the specified,
 //   and set the supplied object handle to point to it.
 //
 // Environment:
 //      Software developed for the BaBar Detector at the SLAC B-Factory.
 //
 // Author List:
 //      Dave Brown     04-24-2000   ( original author )
 //      Igor Gaponenko 05-13-2002   ( adapted for the new Condition/DB )
 //
 // Copyright Information:
 //      Copyright (C) 2000, 2002    Lawrence Berkeley National LAboratory
 //
 //------------------------------------------------------------------------
 */

// prototype for the function required on construction (type pointer-to-function; can be
// a member function of a class, a static function, or a global function).

typedef bool (*CdbBdbCreateCondObject)( const char*,
                                        BdbRefAny&,
                                        BdbRef(BdbObject)& );


class CdbBdbLoadList : public BdbCondProxyBase {

private:

  /// Default constructor (NOT IMPLEMENTED)

    CdbBdbLoadList( );

  /// Assignment operator (NOT IMPLEMENTED)

    CdbBdbLoadList& operator=( const CdbBdbLoadList& theList );

public:

  // construct with subsystem name, container name, and creation function

    CdbBdbLoadList( const char*            sysname,
                    const char*            containername,
                    CdbBdbCreateCondObject function );

  // this class probably doesn't need to be inherited from, but...

    virtual ~CdbBdbLoadList();

  // the real function; pass in the filename, it'll create objects and store them in the
  // conditions DB for you.  Return status is the for the last stored object; if any object
  // fails to be created or stored, the transaction will _not_ be committed, and it
  // will be up to the caller to cleanup.  If every object is successfully created and stored,
  // the transaction will be committed and the return value will be BdbCSuccess

    virtual BdbStatus storeObjects( const char* filename );

private:

  // obvious data members

    std::string _sysname;
    std::string _contname;

    CdbBdbCreateCondObject _createfunction;
};

#endif  // CDBBDB_LOADLIST_HH

---