object-space.md

Object Space

The Object Space is Bold's in-memory object graph where all domain objects live during runtime. It's managed by TBoldSystem and provides:

• Object lifecycle management (create, modify, delete)
• Identity management (each object has a unique ID)
• Change tracking (dirty objects, undo/redo)
• Transaction support

Architecture

classDiagram
    class TBoldSystem {
        +Classes: TBoldClassList
        +DirtyObjects: TBoldObjectList
        +StartTransaction()
        +CommitTransaction()
        +RollbackTransaction()
        +EvaluateExpression()
    }

    class TBoldClassExtent {
        +BoldObjects: TBoldObjectList
        +CreateNewObject()
    }

    class TBoldObject {
        +BoldSystem: TBoldSystem
        +BoldClassTypeInfo: TBoldClassTypeInfo
        +BoldObjectLocator: TBoldObjectLocator
        +Delete()
    }

    TBoldSystem "1" --> "*" TBoldClassExtent : manages
    TBoldClassExtent "1" --> "*" TBoldObject : contains

Loading

Object States

Objects in the Object Space have a state that tracks their lifecycle:

stateDiagram-v2
    [*] --> New: Create
    New --> Clean: SaveToDatabase
    Clean --> Modified: Change attribute
    Modified --> Clean: SaveToDatabase
    Clean --> Deleted: Delete
    Modified --> Deleted: Delete
    Deleted --> [*]: SaveToDatabase

Loading

State	Description
New	Just created, not yet in database
Clean	Matches database, no pending changes
Modified	Has unsaved changes
Deleted	Marked for deletion

Working with Object Space

Accessing the System

var
  System: TBoldSystem;
begin
  System := BoldSystemHandle1.System;
end;

Creating Objects

var
  Customer: TCustomer;
begin
  // Method 1: Using class extent
  Customer := System.Classes['Customer'].CreateNewObject as TCustomer;

  // Method 2: Direct constructor (if generated)
  Customer := TCustomer.Create(System);
end;

Finding Objects

// Get all instances of a class
var
  AllCustomers: TBoldObjectList;
begin
  AllCustomers := System.Classes['Customer'].BoldObjects;
end;

// Find by ID
var
  Customer: TBoldObject;
begin
  Customer := System.ObjectById[SomeId];
end;

Transactions

System.StartTransaction;
try
  // Make changes
  Customer.Name := 'New Name';
  Order.Delete;

  System.CommitTransaction;
except
  System.RollbackTransaction;
  raise;
end;

Class Extents

Each class in your model has a Class Extent - a collection of all instances of that class:

var
  CustomerExtent: TBoldClassExtent;
  Count: Integer;
begin
  CustomerExtent := System.Classes['Customer'];
  Count := CustomerExtent.BoldObjects.Count;
end;

Dirty Objects

Bold tracks which objects have unsaved changes:

// Check if there are unsaved changes
if System.DirtyObjects.Count > 0 then
  ShowMessage('You have unsaved changes');

// Get list of modified objects
for i := 0 to System.DirtyObjects.Count - 1 do
  ProcessDirtyObject(System.DirtyObjects[i]);