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CdbBdbSBtreeP.ddl

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#ifndef CDBBDBSHARED_BTREE_P_HH
#define CDBBDBSHARED_BTREE_P_HH

// File and Version Information:
//      $Id: CdbBdbSBtreeP.ddl,v 1.7 2004/03/24 07:09:30 gapon Exp $

#include "BdbUtil/Bdb.hh"

#include "CdbBdbShared/CdbBdbSAbsBtree.hh"
#include "CdbBdbShared/CdbBdbSPagedVarrayP.hh"

/// This is a persistent implementation for of a B-tree.
/**
  */
template< class K,
          class FCP   = CdbBdbSBtreeDefaultFCP<K>,
          class ORDER = CdbBdbSBtreeDefaultOrder >
class CdbBdbSBtreeP : public BdbPersObj,
                      public CdbBdbSAbsBtree<K,FCP,ORDER> {

private:

  /// Node definition
  /**
    * The only reason to have this definition is to avoid DDL compilation problem
    * for the following definitions:
    *
    *     ooRef( template_class< another_template_class< ... > > )
    */
    typedef CdbBdbSPagedVarrayP< CdbBdbSBtreeNode<K,ORDER> > PagedVarrayOfNodeP;

public:

  // Constructors

    CdbBdbSBtreeP( );

  // Destructor

    virtual ~CdbBdbSBtreeP( );

protected:

  /// Get a root node of the B-tree
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::root()
    */
    virtual d_ULong root( ) const;

  /// Set new root node of the B-tree
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::root()
    */
    virtual void set_root( d_ULong node );

  /// Get a copy of specified node
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::readNode()
    */
    virtual CdbBdbSBtreeNode<K,ORDER> readNode( d_ULong node ) const;

  /// Save back the value of specified node
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::updateNode()
    */
    virtual void updateNode( d_ULong                          node,
                             const CdbBdbSBtreeNode<K,ORDER>& value );

  /// Allocator
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::root()
    */
    virtual d_ULong allocate( d_ULong parent = 0 );

  /// Disposer
  /**
    * Implements the corresponding method of the base class.
    *
    * @see CdbBdbSAbsBtree::root()
    */
    virtual void release( d_ULong node );

private:

  /// This is in fact a normal/default constructor for specified node.
  /**
    * By default the node does not have a parent.
    */
    void init_node( d_ULong node,
                    d_ULong parent );

  /// Extend a list of free nodes
  /**
    * This list is only extended if it's empty.
    */
    void extend_free_list( );

private:

  /// The actual storage.
  /**
    * The first element of the array (index = 0) is not used, because
    * this number is meant to simulate "null pointer".
    *
    * The second element (index = 1) is used as a default root node.
    * This will change as the tree will expand.
    *
    * Initially spare elements begin from the index = 2.
    * This will also change as the tree will expand.
    *
    * NOTE: The use of "OO_COMMA" instead of regual comma symbol. This is due to
    *       the way the BdbRef/ooRef macros get expanded. See Objectivity/DB DDL
    *       manual (page 47) for details.
    */
    BdbRef( PagedVarrayOfNodeP ) _bufRef;

  /// An index of the root node

    d_ULong _root;

  /// An index of the first spare node
  /**
    * These nodes form a linked list. So the first spare node is actually
    * the head of the list.
    */
    d_ULong _free;
};

// Explicit template instantiation for B-Trees of primitive types of elements
//
// NOTE: The sebsequent definitions assume that the corresponding definitions
//       have already been made for Paged V-Array.

#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_1_NOPVARRAY( T ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_1( CdbBdbSBtreeNode< T > ); \
template class CdbBdbSBtreeP< T >

/// Macros for the explicit template instantiation of non-trivial types.
/**
  * The macro will provide all the nessesary declarations for specified
  * type of elements (first paremeter). It will also introduce new type
  * as required by the second parameter.
  *
  * NOTE: Pay attention to the primitive types to avoid declaring them
  *       more than once.
  */
#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_1( T ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_1( T ); \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_1( CdbBdbSBtreeNode< T > ); \
template class CdbBdbSBtreeP< T >

#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_2( T1 , T2 ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_2( T1 , T2 ); \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_2( CdbBdbSBtreeNode< T1 , T2 > ); \
template class CdbBdbSBtreeP              < T1 , T2 >

#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_3( T1 , T2 , T3 ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_3( T1 , T2 , T3 ); \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_3( CdbBdbSBtreeNode< T1 , T2 , T3 > ); \
template class CdbBdbSBtreeP              < T1 , T2 , T3 >

#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_1_FCP_1( T , FCP ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_1( T ); \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_1( CdbBdbSBtreeNode< T > ); \
template class CdbBdbSBtreeP              < T , FCP >

#define EXPLICIT_INSTANTIATE_CdbBdbSBtreeP_2_FCP_2( T1 , T2 , FCP1 , FCP2 ) \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_2( T1 , T2 ); \
EXPLICIT_INSTANTIATE_CdbBdbSPagedVarrayP_2( CdbBdbSBtreeNode< T1 , T2 > ); \
template class CdbBdbSBtreeP              < T1 , T2 , FCP1 , FCP2 >

// Template class implementation

#ifdef    BABAR_COMP_INST
#include "CdbBdbShared/CdbBdbSBtreeP.cc"
#endif /* BABAR_COMP_INST */

#endif /* CDBBDBSHARED_BTREE_P_HH */

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