In Oracle ADF, a task flow is a visual and declarative way to define the navigation and control flow of an application. It essentially orchestrates the sequence of activities that a user performs within an application, providing a structured and reusable approach to building user interfaces.
Here's a breakdown of what a task flow is and its key characteristics:
Core Concept:
- Navigation and Control Flow:
- A task flow defines the sequence of views (pages), activities (business logic), and transitions (navigation rules) that make up a user's interaction with an application.
- Visual Representation:
- ADF provides a visual editor for creating task flows, allowing developers to drag and drop components to design the application's navigation.
- Reusable Components:
- Task flows can be designed as reusable components, enabling developers to create modular and maintainable applications.
- Transaction Management:
- Task flows can manage transactions, ensuring data consistency and integrity.
- Parameter Passing:
- Task flows allow for the passing of parameters between views and activities, enabling data to be shared across different parts of the application.
Key Components of a Task Flow:
- View Activities:
- These represent the user interface pages (JSF pages) that are displayed to the user.
- Method Call Activities:
- These invoke business logic methods within ADF Business Components or other Java classes.
- Router Activities:
- These define conditional navigation based on specific criteria.
- Control Flow Cases:
- These define the transitions between activities, specifying the conditions that trigger each transition.
- Task Flow Call Activities:
- These activities call other task flows, allowing for nested and reusable task flow structures.
- Return Activities:
- These activities are used to exit a task flow and return control to the calling task flow or application.
- Data Control Scope:
- Task flows define the scope of data controls, controlling the accessibility of data within the task flow.
Types of Task Flows:
- Bounded Task Flows:
- These are self-contained task flows that have a defined entry and exit point. They can be reused across different parts of an application.
- Unbounded Task Flows:
- These are the main task flows of an application, providing the overall navigation structure.
Benefits of Using Task Flows:
- Improved Application Structure:
- Task flows provide a structured and organized approach to application development.
- Enhanced Reusability:
- Reusable task flows reduce development time and improve maintainability.
- Simplified Navigation Management:
- Task flows simplify the management of complex navigation scenarios.
- Increased Developer Productivity:
- The visual editor and declarative approach of task flows improve developer productivity.
In essence, task flows are a fundamental building block in Oracle ADF, providing a powerful and flexible way to design and manage the navigation and control flow of enterprise applications.
