BuilderFromVariant< ObjectType > Class Template Reference

Base class for Builders that can build from value::Variant. More...

#include <keyvalue/mngt/BuilderFrom.h>

List of all members.

Public Member Functions
shared_ptr< ObjectType >	getObject (const value::Variant &data) const
	Gets the object built by the derived Builder.
Private Member Functions
virtual const char *	getName () const =0
template<typename InputType >
shared_ptr< ObjectType >	build (const value::Variant &data) const
	Called by getObject.

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Detailed Description

template<typename ObjectType>
class keyvalue::BuilderFromVariant< ObjectType >

Base class for Builders that can build from value::Variant.

Any Builder which can build from value::Variant must derive from this class. Additionally, it also must derive from at least one instantiation of template class BuilderFrom.

Parameters:

ObjectType

: (template parameter) Type of object build by the derived Builder.

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Member Function Documentation

shared_ptr< ObjectType > getObject

(

const value::Variant &

data

)

const

Gets the object built by the derived Builder.

In general, the data that builders need to perform their duties is so rich that must be stored in a DataSet. Nevertheless, in some particular cases, a single value::Variant might be enough. For instance, consider a builder that creates a curve given a few points on it. Normally, this processor needs the set of points together with interpolator and extrapolator methods. In this general case, a DataSet is necessary to hold all this information. However, when the curve is known to be constant, then a single number - the constant - is enough to build the whole curve. Rather than creating a DataSet to store a single double value, it would be more convenient if the processor could accept just this value (or more generally, a value::Variant). That is the reason for this method.

Given the content type InputType of the provided value::Variant and assuming that the dynamic type of the derived object is BuilderFrom<ObjectType, InputType>, this method forwards its call to BuilderFrom<ObjectType, InputType>::getObject().

Parameters:

data

: The input value::Variant.

Returns:

The object built by the derived Builder.

Exceptions:

LogicError

: If the dynamic type of the derived object is not BuilderFrom<ObjectType, InputType>.

shared_ptr< ObjectType > build

(

const value::Variant &

data

)

const [private]

Called by getObject.

See the documentation of getObject(). Actually, that method only detects InputType and then call this one.

Parameters:

data

: The input value::Variant.

Returns:

The object built by the derived Builder.

@ throw LogicError : If the dynamic type of this is not BuildFrom<ObjectType, InputType>.