FDO API Reference

Feature Data Objects

PropertyValueConstraintList.h

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#ifndef _PROPERTYVALUECONSTRAINTLIST_H_
#define _PROPERTYVALUECONSTRAINTLIST_H_

//
// Copyright (C) 2004-2006  Autodesk, Inc.
// 
// This library is free software; you can redistribute it and/or
// modify it under the terms of version 2.1 of the GNU Lesser
// General Public License as published by the Free Software Foundation.
// 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
// 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
//

#ifdef _WIN32
#pragma once
#endif

#include <FdoStd.h>
#include <Fdo/Schema/PropertyValueConstraint.h>
#include <Fdo/Expression/DataValueCollection.h>

/// \brief
/// FdoPropertyValueConstraintList is used to specify a list of allowed values for a particular property. 
/// It can be used for all data property types except for Boolean, BLOB, or CLOB.
/// This constraint is represented by a list of values of the same type as the corresponding data property. 
/// The list cannot be empty. The list could be a single value. While that may not seem very useful it could serve as a 
/// temporary way to enforce a single value for a property, e.g. for a particular customer, Parcel.State is always 'CA' 
/// In this case, the definer of the property definition probably should also set the default value to be the same, unless it can be null.
/// The list does not need to be ordered. However, a provider may choose to reorder the list so the list that is returned when 
/// a user gets the definition of this constraint for a property may be different than the order that was given when defined.
/// E.g. defined as (12, 8, 24), but returned as (8, 12, 24). If the list has duplicate values, the provider may choose to eliminate 
/// duplicates from the list.
/// If the data property definition allows nulls, a null value is considered as being valid regardless of this list of valid values. 
/// The list of valid values should not include the null value itself, but leave the specification of whether null is allowed to 
/// the null value constraint. If the data property definition includes a non-null default value, then that value should be one 
/// of the values in the list.
/// If both a valid values list constraint and a unique constraint on the same property are included, then the side effect is that 
/// there will be an upper limit of the number of objects of that class that have non-null values for the property.
class FdoPropertyValueConstraintList : public FdoPropertyValueConstraint
{
    friend class FdoInternalPropertyValueConstraintList;

protected:
    /// Constructs a default instance of a FdoPropertyValueConstraintList.
    FdoPropertyValueConstraintList();

    virtual ~FdoPropertyValueConstraintList();

    virtual void Dispose()
    {
        delete this;
    }
public:
    
    /// \brief
    /// Constructs an empty instance of an FdoPropertyValueConstraintList.
    /// 
    /// \return
    /// Returns an FdoPropertyValueConstraintList
    /// 
    FDO_API static FdoPropertyValueConstraintList* Create( );

    /// \brief
    /// Returns the list of allowed values for a particular property.
    /// 
    /// \return
    /// Returns na instance of FdoDataValueCollection.
    /// 
    FDO_API FdoDataValueCollection* GetConstraintList();

    /// \brief
    /// Returns FdoPropertyValueConstraintType_Range type.
    /// 
    /// \return
    /// Returns the constraint type
    /// 
    FDO_API virtual FdoPropertyValueConstraintType GetConstraintType();

/// \cond DOXYGEN-IGNORE
    // Public non-API functions for XML and Schema Merge support

    /// Update this list constraint from the given value constraint.
    virtual void Set( FdoPropertyValueConstraint* pProperty, FdoString* parentName, FdoSchemaMergeContext* pContext );

    // \brief
    // Compares this list constraint with another one.
    // 
    // \param value 
    // The Property Value constraint to compare with
    // 
    // \return
    // Returns true if this list constraint is the same as pConstraint
    // (same constraint type and all members have the same values).
    virtual bool Equals( FdoPropertyValueConstraint* pConstraint );

private:
    // Builds dictionary from given data values, filtering out duplicates.
    FdoDictionaryP ValuesToDictionary( FdoDataValueCollection* values );
    
    FdoDataValueCollection* m_constraintList;
/// \endcond
};
#endif

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