RTT::TemplateTypeInfo< T, use_ostream > Class Template Reference

This helper class allows user types to be added to Orocos. More...

#include <rtt/TemplateTypeInfo.hpp>

Inheritance diagram for RTT::TemplateTypeInfo< T, use_ostream >:

Public Types
typedef T	UserType
	The given T parameter is the type for reading DataSources.
typedef Property< T > ::DataSourceType	PropertyType
	When Properties of T are constructed, they are non-const, non-reference.
Public Member Functions
	TemplateTypeInfo (std::string name)
	Setup Type Information for type name.
AttributeBase *	buildConstant (std::string name, DataSourceBase::shared_ptr dsb) const
	Build a non modifyable instance of this type.
AttributeBase *	buildVariable (std::string name) const
	Build a non modifyable instance of this type.
AttributeBase *	buildAttribute (std::string name, DataSourceBase::shared_ptr in) const
	Build an Attribute of this type.
AttributeBase *	buildAlias (std::string name, DataSourceBase::shared_ptr in) const
	build an alias with b as the value.
virtual const std::string &	getTypeName () const
	Return unique the type name.
virtual PropertyBase *	buildProperty (const std::string &name, const std::string &desc, DataSourceBase::shared_ptr source=0) const
	Build a Property of this type.
virtual DataSourceBase::shared_ptr	buildValue () const
	Build a ValueDataSource of this type.
virtual std::ostream &	write (std::ostream &os, DataSourceBase::shared_ptr in) const
	Output this datasource as a human readable string.
virtual std::istream &	read (std::istream &os, DataSourceBase::shared_ptr out) const
	Read a new value for this datasource from a human readable string.
virtual bool	decomposeType (DataSourceBase::shared_ptr source, PropertyBag &targetbag) const
	Decompose a structure as basic components into a PropertyBag.
virtual bool	decomposeTypeImpl (typename AssignableDataSource< T >::const_reference_t source, PropertyBag &targetbag) const
	User, implement this function.
virtual bool	composeType (DataSourceBase::shared_ptr source, DataSourceBase::shared_ptr result) const
	Compose a structure from a PropertyBase containing its basic components.
virtual bool	composeTypeImpl (const PropertyBag &source, typename AssignableDataSource< T >::reference_t result) const
	User, implement this function.
std::string	getTypeIdName () const
Type building/factory functions
Used to create objects that hold data of a certain type.
virtual AttributeBase *	buildConstant (std::string name, DataSourceBase::shared_ptr, int sizehint) const
	Build a non modifyable instance of this type.
virtual AttributeBase *	buildVariable (std::string name, int sizehint) const
	Build a modifyable instance of this type.
virtual DataSourceBase::shared_ptr	construct (const std::vector< DataSourceBase::shared_ptr > &args) const
	Constructor syntax: construct a DataSource which returns an instance of data depending on the given arguments.
virtual DataSourceBase::shared_ptr	convert (DataSourceBase::shared_ptr arg) const
	Automatic conversion: convert a DataSource to this type.
virtual void	addConstructor (TypeBuilder *tb)
	Add a constructor/convertor object.
Conversion to/from text
Used to convert data to human readable text and vice versa.
virtual std::string	toString (DataSourceBase::shared_ptr in) const
	Usability function which converts data to a string.
virtual bool	fromString (const std::string &value, DataSourceBase::shared_ptr out) const
	Usability function which converts a string to data.
Distribution of objects
Used to transport data over a network.
bool	addProtocol (int protocol_id, detail::TypeTransporter *tt)
	Register a protocol for data transport over a network.
detail::TypeTransporter *	getProtocol (int protocol_id) const
	Register a protocol for data transport over a network.
std::vector< int >	getTransportNames () const
	Return a list of protocols that have transporters.
Protected Types
typedef std::vector < TypeBuilder * >	Constructors
typedef std::vector < detail::TypeTransporter * >	Transporters
Protected Attributes
Constructors	constructors
Transporters	transporters

Detailed Description

template<typename T, bool use_ostream = false>
class RTT::TemplateTypeInfo< T, use_ostream >

This helper class allows user types to be added to Orocos.

It provides 'default' implementations for each conversion type. For user defined types, this is very likely not satisfactory and the user needs to override the methods of this class in a subclass or provide specialised global functions.

Parameters:

	T	The user class type.
	ParamT	The type used to pass the value as a parameter. This defaults to T, but if T allocates upon copy (like std::string or std::vector), ParamT tells Orocos how to pass it, probably by const& or &.
	use_ostream	When set to true, the class will use operator<<(std::ostream&, T) to write out the type to a stream. When set to false, the class will use this function and write '( type name )' to a stream instead. Defaults to false. Set to true if your class T has the above mentioned function.

See also:: TypeInfoRepository.; composeType; decomposeType; operator<<

composeTypeImpl() and decomposeTypeImpl()

The decomposeTypeImpl function is a function which converts user data into property bags of native C++ primitive types. The primitive types are then typically used to write the data to screen or to disk. The inverse operation is done by composeTypeImpl, which reassembles a Property from its composite parts.

Every new user type used as a property will require these two functions if it must be 'written to a file'. The subclass must implement these functions by using composeTypeImpl() and decomposeTypeImpl(). such that class T is decomposed in primitive property types.

Example for type MyClass :

  struct MyClass {
      bool var1;
      double var2;
  };

  bool decomposeTypeImpl(const MyClass &c, PropertyBag& result)
  {
      // Decode c into primitive properties Var1 and Var2 which are in a PropertyBag of the
      // bag-type "MyClass" with the same name as the Property 'c'.
        result.setType("MyClass");

      // Put var1 and var2 in the bag
      result.add( new Property<bool>("Var1","Description", c.var1 );
      result.add( new Property<double("Var2","Description", c.var2 );

      return true; // done !
  }
  bool composeTypeImpl(const PropertyBag& bag, MyClass &result)
  {
      // Read the variables from the bag and write them to result.
        if ( bag.getType() != "MyClass") {
         std::cerr << "Wrong type encountered when composing "<< this->getTypeName()<<std::endl;
         return false;
      }
      if ( bag.find("Var1") == 0 || bag.find("Var2") == 0 ) {
         std::cerr << "Missing properties when composing "<< this->getTypeName()<<std::endl;
         return false;
      }
      // Read var1 and var2 from the bag
      result.var1 = bag.getProperty<bool>("Var1")->get();
      result.var2 = bag.getProperty<bool>("Var2")->get();

      return true; // done !
  }

Definition at line 161 of file TemplateTypeInfo.hpp.

Constructor & Destructor Documentation

template<typename T, bool use_ostream = false>

RTT::TemplateTypeInfo< T, use_ostream >::TemplateTypeInfo ( std::string name ) [inline]

Setup Type Information for type name.

This causes a switch from 'unknown' type to basic type information for type T.

Parameters:

name

the 'Orocos' type name.

Definition at line 185 of file TemplateTypeInfo.hpp.

Member Function Documentation

template<typename T, bool use_ostream = false>

AttributeBase* RTT::TemplateTypeInfo< T, use_ostream >::buildAlias	(	std::string	name,
		DataSourceBase::shared_ptr	b
	)			const `[inline, virtual]`

build an alias with b as the value.

If b is of the wrong type, 0 will be returned..

Implements RTT::TypeInfo.

Definition at line 232 of file TemplateTypeInfo.hpp.

virtual AttributeBase* RTT::TypeInfo::buildConstant	(	std::string	name,
		DataSourceBase::shared_ptr	,
		int	sizehint
	)			const `[virtual, inherited]`

Build a non modifyable instance of this type.

Parameters:

sizehint

For variable size instances, use it to hint the size of the instance.

template<typename T, bool use_ostream = false>

AttributeBase* RTT::TemplateTypeInfo< T, use_ostream >::buildConstant	(	std::string	name,
		DataSourceBase::shared_ptr
	)			const `[inline, virtual]`

Build a non modifyable instance of this type.

Parameters:

sizehint

For variable size instances, use it to hint the size of the instance.

Implements RTT::TypeInfo.

Definition at line 198 of file TemplateTypeInfo.hpp.

virtual AttributeBase* RTT::TypeInfo::buildVariable	(	std::string	name,
		int	sizehint
	)			const `[virtual, inherited]`

Build a modifyable instance of this type.

Parameters:

sizehint

For variable size instances, use it to hint the size of the instance.

Reimplemented in RTT::TemplateContainerTypeInfo< T, IndexType, SetType, IPred, APred, has_ostream >, and RTT::TemplateContainerTypeInfo< std::vector< T >, int, T, ArrayIndexChecker< std::vector< T > >, SizeAssignChecker< std::vector< T > >, has_ostream >.

template<typename T, bool use_ostream = false>

AttributeBase* RTT::TemplateTypeInfo< T, use_ostream >::buildVariable ( std::string name ) const [inline, virtual]

Build a non modifyable instance of this type.

Parameters:

sizehint

For variable size instances, use it to hint the size of the instance.

Implements RTT::TypeInfo.

Reimplemented in RTT::TemplateContainerTypeInfo< T, IndexType, SetType, IPred, APred, has_ostream >, RTT::TemplateIndexTypeInfo< T, IndexType, SetType, IPred, APred, has_ostream >, and RTT::TemplateContainerTypeInfo< std::vector< T >, int, T, ArrayIndexChecker< std::vector< T > >, SizeAssignChecker< std::vector< T > >, has_ostream >.

Definition at line 211 of file TemplateTypeInfo.hpp.

template<typename T, bool use_ostream = false>

virtual bool RTT::TemplateTypeInfo< T, use_ostream >::composeType	(	DataSourceBase::shared_ptr	source,
		DataSourceBase::shared_ptr	target
	)			const `[inline, virtual]`

Compose a structure from a PropertyBase containing its basic components.

The default behavior tries to assign source to target. If this does not work, because source and target have different type, this function returns false.

Implements RTT::TypeInfo.

Definition at line 296 of file TemplateTypeInfo.hpp.

template<typename T, bool use_ostream = false>

virtual bool RTT::TemplateTypeInfo< T, use_ostream >::composeTypeImpl	(	const PropertyBag &	source,
		typename AssignableDataSource< T >::reference_t	result
	)			const `[inline, virtual]`

User, implement this function.

Extract the structural elements in source to result.

Definition at line 322 of file TemplateTypeInfo.hpp.

Referenced by RTT::TemplateTypeInfo< std::vector< T >, has_ostream >::composeType().

virtual DataSourceBase::shared_ptr RTT::TypeInfo::construct ( const std::vector< DataSourceBase::shared_ptr > & args ) const [virtual, inherited]

Constructor syntax: construct a DataSource which returns an instance of data depending on the given arguments.

When args is empty, the default 'variable' is returned.

Reimplemented in RTT::EmptyTypeInfo.

virtual DataSourceBase::shared_ptr RTT::TypeInfo::convert ( DataSourceBase::shared_ptr arg ) const [virtual, inherited]

Automatic conversion: convert a DataSource to this type.

For example, for converting float -> double. If no valid conversion was found, returns arg again, otherwise, a new data source.

template<typename T, bool use_ostream = false>

virtual bool RTT::TemplateTypeInfo< T, use_ostream >::decomposeType	(	DataSourceBase::shared_ptr	source,
		PropertyBag &	targetbag
	)			const `[inline, virtual]`

Decompose a structure as basic components into a PropertyBag.

Return values:

	true	decomposition resulted in new types added to targetbag.
	false	nothing was added to targetbag.

Implements RTT::TypeInfo.

Definition at line 280 of file TemplateTypeInfo.hpp.

template<typename T, bool use_ostream = false>

virtual bool RTT::TemplateTypeInfo< T, use_ostream >::decomposeTypeImpl	(	typename AssignableDataSource< T >::const_reference_t	source,
		PropertyBag &	targetbag
	)			const `[inline, virtual]`