GroupReader

The class GroupReader is an abstractt base class for the classes that read environment fata from a qdf file’s environment groups.

This file also defines a base class for group attributes:

struct Attributes {
    uint m_iNumCells;
};

The classes derived from GroupReader will use the structs derived from Attributes

GroupReader is a template class with two templates

template<class T, typename U>
class GroupReader;

T will be instantiated with an environemnt class, U will be instantiated with a class derived from Attribute

The environment classes are SCellGrid, Geography, Climate, Vegetation, Navigation.

Code:
GroupReader.h
GroupReader.cpp

Public Methods

destructor

virtual ~GroupReader();

The destructor closes all open HDF handles.

readAttributes

virtual int readAttributes(U *pAttributes);

Reads the attributes for the group into pAttributes.

pAttributes

A pointer to a class derived from Attributes.

Returns 0 on success, -1 otherwise.

readArray

virtual int readArray(T *pGroup, const std::string sArrayName)=0;

A virtual function intended to read an array from the group in the qdf file into the corresponding array of the group.

This method must be implemented in derived classes.

pGroup

A pointer to an environment class.

sArrayName

The name of an array in the environment class (the same name being used in the qdf file)

Returns 0 on success, -1 otherwise.

readData

virtual int readData(T *pGroup)=0;

A virtual function intended to read all arrays from the group in the qdf file into the corresponding arrays of the group.

This class must be implemented in derived classes.

pGroup

A pointer to an environment class.

Returns 0 on success, -1 otherwise.

ProtectedMethods

constructor

GroupReader()

The constructor initializes the members.

init

virtual int init(const std::string sFileName, const std::string sGroupName);
virtual int init(hid_t hFile, const std::string sGroupName);

Opens the qdf file and gets a handle to the group.

These methods may be overwritten if necessary (but normally they suffice).

sFileName

Name of the qdf file to open.

hFile

HDF handle to a qdf file.

sGroupName

The name of the environment group to open.

Returns 0 on success, -1 otherwise.

tryReadAttributes

virtual int tryReadAttributes(U *pAttributes);

Does the actual reading of the attributes when called by readAttributes. Here it simply the number of cells.

This method should be implemented in derived classes to take into account the particular attributes of the group.

pAttributes

A pointer to a class derived from Attributes.

Returns 0 on success, -1 otherwise.