---

# (DD02) Business Logic — Sortingss.main() [12 LOC]

| Field | Value |
|-------|-------|
| Fully Qualified Name | `algo_Calc.Sortingss` |
| Layer | Utility |
| Module | `algo_Calc` (Package: `algo_Calc`) |

## 1. Role

### Sortingss.main()

This method is the desktop application entry point for the `Sortingss` screen. Its business purpose is not to perform sorting itself, but to start the user interface safely on the AWT event dispatch thread so that the application window is created and displayed in a Swing-compatible way. The method implements a simple launch-and-display pattern: it schedules a `Runnable`, instantiates the main window, and makes the window visible to the user.

The method also provides a minimal error-handling boundary around UI bootstrap. If the window construction or display sequence fails, the exception is caught and its stack trace is printed, allowing startup failures to be observed during development or operations troubleshooting. There are no domain branches, CRUD transactions, or data transformations in this method; its only responsibility is application activation and screen presentation.

## 2. Processing Pattern (Detailed Business Logic)

```mermaid
flowchart TD
    START(["main(args)"])
    INVOKE(["EventQueue.invokeLater(new Runnable())"])
    RUN(["Runnable.run()"])
    TRY(["try block"])
    NEW_WINDOW(["Sortingss window = new Sortingss()"])
    SHOW(["window.frame.setVisible(true)"])
    CATCH(["catch (Exception e)"])
    PRINT(["e.printStackTrace()"])
    END_NODE(["Application launch scheduled / complete"])

    START --> INVOKE
    INVOKE --> RUN
    RUN --> TRY
    TRY --> NEW_WINDOW
    NEW_WINDOW --> SHOW
    SHOW --> END_NODE
    TRY --> CATCH
    CATCH --> PRINT
    PRINT --> END_NODE
```

## 3. Parameter Analysis

| No | Parameter Name | Type | Business Description |
|----|---------------|------|---------------------|
| 1 | `args` | `String[]` | Command-line arguments passed at application startup. In this method, they are accepted by the entry signature but not inspected or used to alter launch behavior. |

**External state read by the method:**
- `Sortingss.frame` via the newly created window instance, when calling `window.frame.setVisible(true)`.
- Java AWT `EventQueue`, which controls deferred UI execution on the event dispatch thread.

## 4. CRUD Operations / Called Services

This method does not perform business CRUD operations and does not call application services or persistence components. The only callable actions are UI framework/bootstrap operations and exception logging.

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|-----------------------|
| R | `EventQueue.invokeLater` | N/A | N/A | Schedules UI creation on the AWT event dispatch thread. This is framework-level execution control, not data read. |
| C | `new Sortingss()` | N/A | N/A | Constructs the main application window object and initializes the screen. |
| U | `window.frame.setVisible(true)` | N/A | N/A | Updates the UI state by making the main frame visible to the user. |
| R | `e.printStackTrace()` | N/A | N/A | Reads and outputs the exception stack trace for troubleshooting. |

## 5. Dependency Trace

| # | Caller (Screen/Batch) | Call Chain (Full Path to this Method) | Terminal (SC / CRUD / Entity) |
|---|----------------------|--------------------------------------|-------------------------------|
| 1 | Screen: `Frame` | `Frame.main` -> `Sortingss.main` | `new Sortingss() [C] N/A` |
| 2 | Direct application launch | JVM launcher -> `Sortingss.main` | `window.frame.setVisible(true) [U] N/A` |

## 6. Per-Branch Detail Blocks

**Block 1** — `TRY` `(inside EventQueue.invokeLater Runnable)` (L171)

> Launches the UI initialization work asynchronously on the Swing event thread.

| # | Type | Code |
|---|------|------|
| 1 | CALL | `EventQueue.invokeLater(new Runnable() { ... });` |

**Block 1.1** — `TRY` `(inside Runnable.run())` (L172-L179)

> Executes the startup workflow that creates and displays the main window.

| # | Type | Code |
|---|------|------|
| 1 | CALL | `Sortingss window = new Sortingss();` |
| 2 | EXEC | `window.frame.setVisible(true);` |

**Block 1.1.1** — `TRY` `(window construction and display)` (L174-L176)

> Attempts to initialize the application window and present it to the user.

| # | Type | Code |
|---|------|------|
| 1 | SET | `Sortingss window = new Sortingss();` |
| 2 | EXEC | `window.frame.setVisible(true);` |

**Block 1.2** — `CATCH` `(catch (Exception e))` (L177-L179)

> Handles any failure during window creation or display and emits diagnostic output.

| # | Type | Code |
|---|------|------|
| 1 | CALL | `e.printStackTrace();` |

## 7. Glossary

| Term | Type | Business Meaning |
|------|------|------------------|
| `args` | Field/Parameter | Command-line arguments supplied at application startup. They are accepted for standard Java entry-point compatibility but are not used by this method. |
| `EventQueue` | Technical term | Java AWT event dispatch queue used to execute UI operations on the correct thread. |
| `Runnable` | Technical term | Java callback interface representing the deferred startup task. |
| `frame` | UI field | Main application window container that becomes visible to the user. |
| `setVisible(true)` | UI operation | Displays the window on screen and makes the application accessible to the user. |
| `printStackTrace()` | Technical term | Outputs exception details for troubleshooting startup failures. |
| UI | Acronym | User Interface — the visible screen used by end users to interact with the application. |
| AWT | Acronym | Abstract Window Toolkit — Java desktop UI foundation used to manage the event dispatch thread. |
| Swing | Acronym | Java desktop UI toolkit used for building the application window. |
| entry point | Technical term | The first method invoked when the application starts. |
| launch | Business term | Application startup sequence that creates the main screen and prepares it for user interaction. |