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Files | Data Structures | Macros | Typedefs | Functions

QOF Objects provide the means for associating a storage backend to a set of QOF Entities. More...

Files

file  qofobject.h
 the Core Object Registration/Lookup Interface
 

Data Structures

struct  QofObject
 This is the QofObject Class descriptor. More...
 

Macros

#define QOF_OBJECT_VERSION   3
 Defines the version of the core object object registration interface. More...
 
#define QOF_MOD_OBJECT   "qof.object"
 

Typedefs

typedef void(* QofForeachCB) (gpointer obj, gpointer user_data)
 
typedef void(* QofForeachTypeCB) (QofObject *type, gpointer user_data)
 
typedef void(* QofForeachBackendTypeCB) (QofIdTypeConst type, gpointer backend_data, gpointer user_data)
 

Functions

gboolean qof_object_register (const QofObject *object)
 Register new types of object objects.
 
const QofObject * qof_object_lookup (QofIdTypeConst type_name)
 Lookup an object definition.
 
gpointer qof_object_new_instance (QofIdTypeConst type_name, QofBook *book)
 Create an instance of the indicated type, returning a pointer to that instance. More...
 
const char * qof_object_get_type_label (QofIdTypeConst type_name)
 Get the printable label for a type. More...
 
const char * qof_object_printable (QofIdTypeConst type_name, gpointer instance)
 
void qof_object_foreach_type (QofForeachTypeCB cb, gpointer user_data)
 Invoke the callback 'cb' on every object class definition. More...
 
void qof_object_foreach (QofIdTypeConst type_name, QofBook *book, QofInstanceForeachCB cb, gpointer user_data)
 Invoke the callback 'cb' on every instance ov a particular object type. More...
 
void qof_object_foreach_sorted (QofIdTypeConst type_name, QofBook *book, QofInstanceForeachCB cb, gpointer user_data)
 Invoke callback 'cb' on each instance in guid orted order.
 

Initialize the object registration subsystem

void qof_object_initialize (void)
 
void qof_object_shutdown (void)
 

Detailed Description

QOF Objects provide the means for associating a storage backend to a set of QOF Entities.

While an entity can be though of as an identified instance of some thing, the QOF Object provides for a way to associate instances with a storage backend. Storage might be file or SQL storage.

QOF Objects are also used by the query system ....

To work with your own QOF Objects, you can use the QOF Generator to create sample objects and a mini-application with the SQL-type query interface. http://qof-gen.sourceforge.net/

XXX todo, we should split out the storage aspects of this thing from the 'foreach' that query depends on. These are kinda unrelated concepts.

Macro Definition Documentation

◆ QOF_OBJECT_VERSION

#define QOF_OBJECT_VERSION   3

Defines the version of the core object object registration interface.

Only object modules compiled against this version of the interface will load properly

Definition at line 63 of file qofobject.h.

Function Documentation

◆ qof_object_foreach()

void qof_object_foreach ( QofIdTypeConst  type_name,
QofBook *  book,
QofInstanceForeachCB  cb,
gpointer  user_data 
)

Invoke the callback 'cb' on every instance ov a particular object type.

It is presumed that the 'book' stores or somehow identifies a colllection of instances; thus the callback will be invoked only for those instances stored in the book.

Definition at line 185 of file qofobject.cpp.

187 {
188  QofCollection *col;
189  const QofObject *obj;
190 
191  if (!book || !type_name)
192  {
193  return;
194  }
195  PINFO ("type=%s", type_name);
196 
197  obj = qof_object_lookup (type_name);
198  if (!obj)
199  {
200  PERR ("No object of type %s", type_name);
201  return;
202  }
203  col = qof_book_get_collection (book, obj->e_type);
204  if (!obj)
205  {
206  return;
207  }
208  if (obj->foreach)
209  {
210  obj->foreach (col, cb, user_data);
211  }
212  return;
213 }
#define PINFO(format, args...)
Print an informational note.
Definition: qoflog.h:256
#define PERR(format, args...)
Log a serious error.
Definition: qoflog.h:244
const QofObject * qof_object_lookup(QofIdTypeConst name)
Lookup an object definition.
Definition: qofobject.cpp:322
QofCollection * qof_book_get_collection(const QofBook *book, QofIdType entity_type)
Return The table of entities of the given type.
Definition: qofbook.cpp:521

◆ qof_object_foreach_type()

void qof_object_foreach_type ( QofForeachTypeCB  cb,
gpointer  user_data 
)

Invoke the callback 'cb' on every object class definition.

The user_data pointer is passed back to the callback.

Definition at line 153 of file qofobject.cpp.

154 {
155  GList *l;
156 
157  if (!cb) return;
158 
159  for (l = object_modules; l; l = l->next)
160  {
161  QofObject *obj = static_cast<QofObject*>(l->data);
162  (cb) (obj, user_data);
163  }
164 }

◆ qof_object_get_type_label()

const char* qof_object_get_type_label ( QofIdTypeConst  type_name)

Get the printable label for a type.

This label is not translated; you must use _() on it if you want a translated version.

Definition at line 263 of file qofobject.cpp.

264 {
265  const QofObject *obj;
266 
267  if (!type_name) return nullptr;
268 
269  obj = qof_object_lookup (type_name);
270  if (!obj) return nullptr;
271 
272  return (obj->type_label);
273 }
const QofObject * qof_object_lookup(QofIdTypeConst name)
Lookup an object definition.
Definition: qofobject.cpp:322

◆ qof_object_new_instance()

gpointer qof_object_new_instance ( QofIdTypeConst  type_name,
QofBook *  book 
)

Create an instance of the indicated type, returning a pointer to that instance.

This routine just calls the (*new) callback on the object definition.

Definition at line 65 of file qofobject.cpp.

66 {
67  const QofObject *obj;
68 
69  if (!type_name) return nullptr;
70 
71  obj = qof_object_lookup (type_name);
72  if (!obj) return nullptr;
73 
74  if (obj->create)
75  return (obj->create (book));
76 
77  return nullptr;
78 }
const QofObject * qof_object_lookup(QofIdTypeConst name)
Lookup an object definition.
Definition: qofobject.cpp:322

◆ qof_object_printable()

const char* qof_object_printable ( QofIdTypeConst  type_name,
gpointer  instance 
)
Returns
a Human-readable string name for an instance

Definition at line 248 of file qofobject.cpp.

249 {
250  const QofObject *b_obj;
251 
252  if (!type_name || !obj) return nullptr;
253 
254  b_obj = qof_object_lookup (type_name);
255  if (!b_obj) return nullptr;
256 
257  if (b_obj->printable)
258  return (b_obj->printable (obj));
259 
260  return nullptr;
261 }
const QofObject * qof_object_lookup(QofIdTypeConst name)
Lookup an object definition.
Definition: qofobject.cpp:322