Chemical Data Processing Library C++ API - Version 1.1.1
Public Types | Public Member Functions | Protected Member Functions | List of all members
CDPL::Base::ControlParameterContainer Class Reference

A class providing methods for the storage and lookup of control-parameter values. More...

#include <ControlParameterContainer.hpp>

+ Inheritance diagram for CDPL::Base::ControlParameterContainer:

Public Types

typedef ParameterMap::value_type ParameterEntry
 A Base::LookupKey / Base::Any pair used to store the control-parameter values and associated keys. More...
 
typedef ParameterMap::const_iterator ConstParameterIterator
 A constant iterator used to iterate over the control-parameter entries. More...
 
typedef std::function< void(const LookupKey &, const Any &)> ParameterChangedCallbackFunction
 A functor class that wraps callback target functions which get invoked when the value of a control-parameter has changed. More...
 
typedef std::function< void(const LookupKey &)> ParameterRemovedCallbackFunction
 A functor class that wraps callback target functions which get invoked when a control-parameter entry has been removed. More...
 
typedef std::function< void()> ParentChangedCallbackFunction
 A functor class that wraps callback target functions which get invoked when the parent container has been changed or was detached. More...
 

Public Member Functions

std::size_t getNumParameters () const
 Returns the number of container entries. More...
 
template<typename T >
void setParameter (const LookupKey &key, T &&val)
 Sets the value of the control-parameter specified by key to val. More...
 
const AnygetParameter (const LookupKey &key, bool throw_=false, bool local=false) const
 Returns the value of the control-parameter specified by key. More...
 
template<typename T >
const T & getParameter (const LookupKey &key, bool local=false) const
 Returns the value of the control-parameter specified by key as a const reference to an object of type T. More...
 
template<typename T >
const T & getParameterOrDefault (const LookupKey &key, const T &def_val, bool local=false) const
 Returns the value of the control-parameter specified by key as a const reference to an object of type T, or the default value def_val if a stored value does not exist. More...
 
bool removeParameter (const LookupKey &key)
 Removes the entry for the control-parameter specified by key. More...
 
void clearParameters ()
 Erases all container entries. More...
 
bool isParameterSet (const LookupKey &key, bool local=false) const
 Tells whether or not a value has been assigned to the control-parameter specified by key. More...
 
void addParameters (const ControlParameterContainer &cntnr)
 Adds the control-parameter value entries in the ControlParameterContainer instance cntnr. More...
 
void copyParameters (const ControlParameterContainer &cntnr)
 Replaces the current set of properties by a copy of the entries in cntnr. More...
 
ConstParameterIterator getParametersBegin () const
 Returns a constant iterator pointing to the beginning of the entries. More...
 
ConstParameterIterator getParametersEnd () const
 Returns a constant iterator pointing to the end of the entries. More...
 
ConstParameterIterator begin () const
 Returns a constant iterator pointing to the beginning of the entries. More...
 
ConstParameterIterator end () const
 Returns a constant iterator pointing to the end of the entries. More...
 
void setParent (const ControlParameterContainer *cntnr)
 Sets or removes the parent control-parameter container used to resolve requests for missing entries. More...
 
const ControlParameterContainergetParent () const
 Returns a pointer to the parent control-parameter container. More...
 
std::size_t registerParameterChangedCallback (const ParameterChangedCallbackFunction &func)
 Registers a callback target function that gets invoked when the value of a control-parameter has changed. More...
 
void unregisterParameterChangedCallback (std::size_t id)
 Unregisters the callback specified by id. More...
 
std::size_t registerParameterRemovedCallback (const ParameterRemovedCallbackFunction &func)
 Registers a callback target function that gets invoked when a control-parameter entry has been removed. More...
 
void unregisterParameterRemovedCallback (std::size_t id)
 Unregisters the callback specified by id. More...
 
std::size_t registerParentChangedCallback (const ParentChangedCallbackFunction &func)
 Registers a callback target function that gets invoked when the parent container has been changed or was detached. More...
 
void unregisterParentChangedCallback (std::size_t id)
 Unregisters the callback specified by id. More...
 
const ControlParameterContainergetParameters () const
 Returns a const reference to itself. More...
 

Protected Member Functions

 ControlParameterContainer ()
 Constructs an empty ControlParameterContainer instance. More...
 
 ControlParameterContainer (const ControlParameterContainer &cntnr)
 Constructs a copy of the ControlParameterContainer instance cntnr. More...
 
virtual ~ControlParameterContainer ()
 Destructor. More...
 
ControlParameterContaineroperator= (const ControlParameterContainer &cntnr)
 Assignment operator. More...
 

Detailed Description

A class providing methods for the storage and lookup of control-parameter values.

The purpose of ControlParameterContainer is to provide a common facility for the storage and lookup of dynamic parameter values to subclasses which can be used to control their runtime-behaviour.

For the explicit assignment of control-parameter values the method setParameter() is provided which expects the key of the control-parameter as its first and the value to assign as the second argument. The availability of a value for a particular control-parameter can be tested by the method isParameterSet(). For the retrieval of control-parameter values the getParameter() family of overloaded methods is provided which expect the key of the control-parameter as an argument. The method getParameterOrDefault() additionally allows to specify a default value that gets returned if an entry for the requested control-parameter value does not exist. ControlParameterContainer guarantees that the complexity of these operations is never worse than logarithmic.

Control-parameter values are stored in an associative map as Base::LookupKey / Base::Any pairs of type ControlParameterContainer::ParameterEntry. The current number of entries can be queried with the method getNumParameters(). Iterators pointing to the beginning and end of the container are obtained via the methods getEntriesBegin() and getEntriesEnd(), respectively.

ControlParameterContainer allows for an arrangement of instances in a tree-like hierarchy where each non-root instance has exactly one parent and zero or more children. In such hierarchies, a child container forwards requests for control-parameter values to their parents if they do not contain a local entry for a given control-parameter. The parent container is set and detached by the method setParent(). A ControlParameterContainer instance automatically keeps track of any links from and to other instances in the hierarchy and detaches any parent or child containers on object destruction.

For the notification of client code about any changes that affect control-parameter values, the ControlParameterContainer interface provides three methods for the registration of callback functions:

Each of these methods returns a numeric identifier for the registered callback function. For callback unregistration purposes the methods unregisterParameterChangedCallback(), unregisterParameterRemovedCallback() and unregisterParentChangedCallback() are provided. These methods require the previously obtained numeric identifier of the callback to be passed as an argument.

Member Typedef Documentation

◆ ParameterEntry

A Base::LookupKey / Base::Any pair used to store the control-parameter values and associated keys.

◆ ConstParameterIterator

A constant iterator used to iterate over the control-parameter entries.

◆ ParameterChangedCallbackFunction

A functor class that wraps callback target functions which get invoked when the value of a control-parameter has changed.

ParameterChangedCallbackFunction allows to wrap any function pointer or function object compatible with a return type of void and two arguments of type const Base::LookupKey& and Base::Any (see [FUNWRP]).

◆ ParameterRemovedCallbackFunction

A functor class that wraps callback target functions which get invoked when a control-parameter entry has been removed.

ParameterRemovedCallbackFunction allows to wrap any function pointer or function object compatible with a return type of void and an argument of type const Base::LookupKey& (see [FUNWRP]).

◆ ParentChangedCallbackFunction

A functor class that wraps callback target functions which get invoked when the parent container has been changed or was detached.

ParentChangedCallbackFunction allows to wrap any function pointer or function object compatible with a return type of void and no arguments (see [FUNWRP]).

See also
setParent()

Constructor & Destructor Documentation

◆ ControlParameterContainer() [1/2]

CDPL::Base::ControlParameterContainer::ControlParameterContainer ( )
inlineprotected

Constructs an empty ControlParameterContainer instance.

◆ ControlParameterContainer() [2/2]

CDPL::Base::ControlParameterContainer::ControlParameterContainer ( const ControlParameterContainer cntnr)
inlineprotected

Constructs a copy of the ControlParameterContainer instance cntnr.

Parameters
cntnrThe ControlParameterContainer instance to copy.
Note
Only the control-parameter entries of cntnr are copied. Entries in the parent container of cntnr (if set) will be ignored (see setParent()).

◆ ~ControlParameterContainer()

virtual CDPL::Base::ControlParameterContainer::~ControlParameterContainer ( )
protectedvirtual

Destructor.

The parent pointer of any children will be set to null before the instance gets destroyed (see setParent()).

Member Function Documentation

◆ getNumParameters()

std::size_t CDPL::Base::ControlParameterContainer::getNumParameters ( ) const

Returns the number of container entries.

Returns
The number of container entries.

◆ setParameter()

template<typename T >
void CDPL::Base::ControlParameterContainer::setParameter ( const LookupKey key,
T &&  val 
)

Sets the value of the control-parameter specified by key to val.

If val is of type Base::Any and empty, i.e. the method Base::Any::isEmpty() returns true, and a control-parameter entry for key exists, the entry gets erased (equivalent to removeParameter() with key as argument). Otherwise the control-parameter is assigned the specified value and any callback functions registered by registerParameterChangedCallback() will be invoked with key and val provided as arguments. Callbacks of affected direct and indirect children which do not have an entry for the specified control-parameter also get invoked.

Parameters
keyThe key of the control-parameter value to assign or remove.
valThe value of the control-parameter.

◆ getParameter() [1/2]

const Any& CDPL::Base::ControlParameterContainer::getParameter ( const LookupKey key,
bool  throw_ = false,
bool  local = false 
) const

Returns the value of the control-parameter specified by key.

If the container contains an entry for the specified control-parameter, the stored value will be returned. If an entry for the control-parameter does not exist, the results depends on the arguments throw_ and local:

If a parent container has been set and the argument local is false, the request is forwarded to the parent (which may also forward the request). Otherwise an empty Base::Any object is returned if _throw is false, and a Base::ItemNotFound exception will be thrown if _throw is true.

Parameters
keyThe key of the control-parameter value to return.
throw_Specifies whether or not to throw a Base::ItemNotFound exception if an entry for the control-parameter does not exist.
localSpecifies whether or not the request shall be forwarded to the parent container if a local entry for the control-parameter does not exist.
Returns
The stored control-parameter value or an empty Base::Any object.
Exceptions
Base::ItemNotFoundif an entry for the requested control-parameter value does not exist and _throw is true.

◆ getParameter() [2/2]

template<typename T >
const T & CDPL::Base::ControlParameterContainer::getParameter ( const LookupKey key,
bool  local = false 
) const

Returns the value of the control-parameter specified by key as a const reference to an object of type T.

If the container contains an entry for the specified control-parameter, the stored value will be returned. If an entry for the control-parameter does not exist, a parent container has been set and the argument local is false, the call is forwarded to the parent (which may also forward the request). Otherwise a Base::ItemNotFound exception will be thrown.

Parameters
keyThe key of the control-parameter value to return.
localSpecifies whether or not the request shall be forwarded to the parent container if a local entry for the control-parameter does not exist.
Returns
The stored control-parameter value as a const reference to an object of type T.
Exceptions
Base::ItemNotFoundif an entry for the requested control-parameter value does not exist, and Base::BadCast if the stored control-parameter value cannot be casted to the target type T.

◆ getParameterOrDefault()

template<typename T >
const T & CDPL::Base::ControlParameterContainer::getParameterOrDefault ( const LookupKey key,
const T &  def_val,
bool  local = false 
) const

Returns the value of the control-parameter specified by key as a const reference to an object of type T, or the default value def_val if a stored value does not exist.

If the container contains an entry for the specified control-parameter, the stored value will be returned. If an entry for the control-parameter does not exist, a parent container has been set and the argument local is false, the call is forwarded to the parent (which may also forward the request). Otherwise the default value specified by def_val is returned.

Parameters
keyThe key of the control-parameter for which to return the stored (or specified default) value.
def_valThe default value that shall be returned if an entry for the specified control-parameter does not exist.
localSpecifies whether or not the request shall be forwarded to the parent container if a local entry for the control-parameter does not exist.
Returns
The stored control-parameter value or the default specified by def_val.
Exceptions
Base::BadCastif the stored control-parameter value cannot be casted to the target type T.

◆ removeParameter()

bool CDPL::Base::ControlParameterContainer::removeParameter ( const LookupKey key)

Removes the entry for the control-parameter specified by key.

If an entry for the control-parameter specified by key exists, the entry is removed and any callback functions registered by registerParameterRemovedCallback() will be invoked with key provided as an argument. Callbacks of affected direct and indirect children which do not have an entry for the specified control-parameter also get invoked.

Parameters
keyThe key of the control-parameter entry to remove.
Returns
true if an entry for key could be found and was removed, and false otherwise.

◆ clearParameters()

void CDPL::Base::ControlParameterContainer::clearParameters ( )

Erases all container entries.

For each container entry, any callback functions registered by registerParameterRemovedCallback() will be invoked with the key of the removed control-parameter entry as an argument. Callbacks of affected direct and indirect children which do not have an entry for the erased control-parameter also get invoked.

◆ isParameterSet()

bool CDPL::Base::ControlParameterContainer::isParameterSet ( const LookupKey key,
bool  local = false 
) const

Tells whether or not a value has been assigned to the control-parameter specified by key.

If the container does not contain an entry for the specified control-parameter, a parent container has been set and the argument local is false, the call is forwarded to the parent (which may also forward the call). Otherwise the result of the local search is returned.

Parameters
keyThe key of the control-parameter.
localSpecifies whether or not the query shall be forwarded to the parent container if a local entry for the control-parameter does not exist.
Returns
true if an entry for the specified control-parameter could be found, and false otherwise.

◆ addParameters()

void CDPL::Base::ControlParameterContainer::addParameters ( const ControlParameterContainer cntnr)

Adds the control-parameter value entries in the ControlParameterContainer instance cntnr.

Any control-parameter values which have no corresponding assigned value in cntnr are left unchanged. Otherwise the value of the local control-parameter gets overwritten by the value stored in cntnr and any callback functions registered by registerParameterChangedCallback() will be invoked with key and value provided as arguments. Callbacks of affected direct and indirect children which do not have an entry for the specified control-parameter also get invoked.

Parameters
cntnrThe ControlParameterContainer instance containing the control-parameter value entries to add.

◆ copyParameters()

void CDPL::Base::ControlParameterContainer::copyParameters ( const ControlParameterContainer cntnr)

Replaces the current set of properties by a copy of the entries in cntnr.

The assignment is equivalent to first erasing all entries by calling clearParameters() and then calling setParameter() for each key/value entry in cntnr.

Parameters
cntnrThe ControlParameterContainer instance containing the control-parameter value entries to add.

◆ getParametersBegin()

ConstParameterIterator CDPL::Base::ControlParameterContainer::getParametersBegin ( ) const

Returns a constant iterator pointing to the beginning of the entries.

Returns
A constant iterator pointing to the beginning of the entries.

◆ getParametersEnd()

ConstParameterIterator CDPL::Base::ControlParameterContainer::getParametersEnd ( ) const

Returns a constant iterator pointing to the end of the entries.

Returns
A constant iterator pointing to the end of the entries.

◆ begin()

ConstParameterIterator CDPL::Base::ControlParameterContainer::begin ( ) const

Returns a constant iterator pointing to the beginning of the entries.

Returns
A constant iterator pointing to the beginning of the entries.

◆ end()

ConstParameterIterator CDPL::Base::ControlParameterContainer::end ( ) const

Returns a constant iterator pointing to the end of the entries.

Returns
A constant iterator pointing to the end of the entries.

◆ setParent()

void CDPL::Base::ControlParameterContainer::setParent ( const ControlParameterContainer cntnr)

Sets or removes the parent control-parameter container used to resolve requests for missing entries.

A control-parameter container that has been set as a parent gets used whenever a request for a control-parameter value cannot be satisfied locally by the container itself. That is, if a key/value entry for a given control-parameter does not exist, the request is simply forwarded to the parent container (which may also forward the request).

Any callback functions registered by registerParentChangedCallback() will be invoked after the new parent container has been set (or the old container was detached by providing a null pointer). Callbacks of any direct and indirect children also get invoked.

Parameters
cntnrA pointer to the parent control-parameter container or null. If the pointer is null, the currently set parent container (if any) gets detached.

◆ getParent()

const ControlParameterContainer* CDPL::Base::ControlParameterContainer::getParent ( ) const

Returns a pointer to the parent control-parameter container.

Returns
A pointer to the parent control-parameter container, or null if no parent container has been set.
See also
setParent()

◆ registerParameterChangedCallback()

std::size_t CDPL::Base::ControlParameterContainer::registerParameterChangedCallback ( const ParameterChangedCallbackFunction func)

Registers a callback target function that gets invoked when the value of a control-parameter has changed.

Parameters
funcA ControlParameterContainer::ParameterChangedCallbackFunction object wrapping the target function.
Returns
An identifier for the registered callback.

◆ unregisterParameterChangedCallback()

void CDPL::Base::ControlParameterContainer::unregisterParameterChangedCallback ( std::size_t  id)

Unregisters the callback specified by id.

If a registered callback with the identifier id does not exist, the method has no effect.

Parameters
idThe identifier of the callback to unregister.

◆ registerParameterRemovedCallback()

std::size_t CDPL::Base::ControlParameterContainer::registerParameterRemovedCallback ( const ParameterRemovedCallbackFunction func)

Registers a callback target function that gets invoked when a control-parameter entry has been removed.

Parameters
funcA ControlParameterContainer::ParameterRemovedCallbackFunction object wrapping the target function.
Returns
An identifier for the registered callback.

◆ unregisterParameterRemovedCallback()

void CDPL::Base::ControlParameterContainer::unregisterParameterRemovedCallback ( std::size_t  id)

Unregisters the callback specified by id.

If a registered callback with the identifier id does not exist, the method has no effect.

Parameters
idThe identifier of the callback to unregister.

◆ registerParentChangedCallback()

std::size_t CDPL::Base::ControlParameterContainer::registerParentChangedCallback ( const ParentChangedCallbackFunction func)

Registers a callback target function that gets invoked when the parent container has been changed or was detached.

Parameters
funcA ControlParameterContainer::ParentChangedCallbackFunction object wrapping the target function.
Returns
An identifier for the registered callback.

◆ unregisterParentChangedCallback()

void CDPL::Base::ControlParameterContainer::unregisterParentChangedCallback ( std::size_t  id)

Unregisters the callback specified by id.

If a registered callback with the identifier id does not exist, the method has no effect.

Parameters
idThe identifier of the callback to unregister.

◆ getParameters()

const CDPL::Base::ControlParameterContainer & CDPL::Base::ControlParameterContainer::getParameters ( ) const
inline

Returns a const reference to itself.

Returns
A const reference to itself.

◆ operator=()

ControlParameterContainer& CDPL::Base::ControlParameterContainer::operator= ( const ControlParameterContainer cntnr)
protected

Assignment operator.

Internally calls copyParameters() to perform the actual work.

Parameters
cntnrThe ControlParameterContainer instance to copy.
Returns
A reference to itself.

The documentation for this class was generated from the following file: