Class Scine::Utils::StatesHandler

class StatesHandler

Class responsible for saving, storing and loading object-specific states.

Core::State is an empty class. This base class is then implemented to have some meaningful definition of a state for an application. I could be, for instance, a density matrix for a Core::Calculator, a partially converged Markov Chain Montecarlo, a checkpoint,… . A Core::StateHandableObject interface exposes the functions for getting and loading a single state. The StatesHandler job is that of storing a list of these states and freely switching between them. This class is stand-alone, but can also be specialized to suit certain needs, this is why it exposes a virtual destructor.

Public Types

using StatesContainer = std::deque<std::shared_ptr<Core::State>>

The data structure in which states are stored.

Public Functions

StatesHandler(std::shared_ptr<Core::StateHandableObject> object = nullptr)

Constructor of the class taking a StateHandableObject instance.

virtual ~StatesHandler()

Virtual default destructor.

void store(std::shared_ptr<Core::State> state)

Store an externally generated state as the newest state.

Parameters

  • state: A pointer to the state to store.

void store()

Stores the current state of the Core::StateHandableObject instance in this class.

void load(std::shared_ptr<Core::State> state)

Loads an externally generated state.

Parameters

  • state: The state to be loaded. The specifics of how exactly the state is stored is not implemented in this class, but is in the Core::StateHandableObject derived class. This just calls the load() method in Core::StateHandableObject instance of this class.

void load(int index)

Loads an internally stored state.

Parameters

  • index: The index of the state to be loaded. The specifics of how exactly the state is stored is not implemented in this class, but is in the Core::StateHandableObject derived class. This just extracts the state and calls the load() method in Core::StateHandableObject instance of this class.

std::shared_ptr<Core::State> getState(int index) const

Gets the state at some index in the StatesContainer.

Return

A polymorphic smart pointer to the Core::State at some index.

std::shared_ptr<Core::State> popOldestState()

Eliminates the oldest state from the StatesContainer and returns it.

std::shared_ptr<Core::State> popNewestState()

Eliminates the newest state from the underlying container and returns it.

void clear()

Clears all the internally saved states.

int size() const

Gets the current size of the state storage.