source: pacpusframework/trunk/include/Pacpus/kernel/ComponentBase.h@ 3

// *********************************************************************
// created:     2006/02/07 - 11:59
// filename:    component.h
//
// author:      Gerald Dherbomez
//
// purpose:     generic ComponentBase class. This is an abstract class
//
// todo:        - see if some methods can be private with ComponentManager
//              friendship
//              - include the copy of Xml node in param here
//              - see if there is a possibility to avoid the constraint
//              on parameters in the constructor of derived class
// *********************************************************************

#ifndef COMPONENTBASE_H
#define COMPONENTBASE_H

#include "kernel/ComponentManager.h" // FIXME: remove this line when all components include it
#include "kernel/pacpus.h"
#include "XmlComponentConfig.h"

#include <QString>

namespace pacpus {

class ComponentManager;

class PACPUSLIB_API ComponentBase
{
    friend class ComponentManager;

public:
    // Here is the enumeration of the state that can take a component
    // The 3 last states suppose that the component is started
    enum COMPONENT_STATE
    {
        STOPPED,
        NOT_MONITORED,
        MONITOR_OK,
        MONITOR_NOK
    };

    // The different identifying the configuration of the component
    enum COMPONENT_CONFIGURATION
    {
        CONFIGURED_OK,
        NOT_CONFIGURED,
        CONFIGURATION_DELAYED,
        CONFIGURED_FAILED
    };

    // constructor - your derived component must have only one parameter
    // in its constructor which is name
    ComponentBase(QString name);

    // destructor
    virtual ~ComponentBase();

    // return the state of the component
    COMPONENT_STATE getState();

    // return true if the component is configured, false else
    inline bool isConfigured()
    {
        return (CONFIGURED_OK == configuration_);
    }

protected:
    // define the state of the component
    void setState(COMPONENT_STATE state);

    // pure virtual function - what to do when the component starts?
    virtual void startActivity() = 0;

    // pure virtual function - what to do when the component stops?
    virtual void stopActivity() = 0;

    // This function is called by the ComponentManager when it loads the XML file
    // It gives to the component the XML node corresponding to its
    // So the component can handle some properties defined in the XML config file
    // via XmlComponentConfig methods
    virtual COMPONENT_CONFIGURATION configureComponent(pacpus::XmlComponentConfig config) = 0;

    // The XML node that is got in the configureComponent method
    pacpus::XmlComponentConfig param;

    // the name of the component. It is this one in the XML config file
    QString componentName;

    // is the component is recording data?
    bool recording;

    // provided for compatibility with old DBITE framework
    bool THREAD_ALIVE;

    // is the component active?
    bool mIsActive;

    // a pointer to the manager of components
    ComponentManager * mgr;

private:
    // called by the ComponentManager to start the component
    int startComponent();

    // called by the ComponentManager to stop the component
    int stopComponent();

    // store the state of the component
    COMPONENT_STATE componentState_;

    // is the component configured (ie configureComponent method was called)
    COMPONENT_CONFIGURATION configuration_;
};

} // namespace pacpus

#endif // COMPONENTBASE_H