ADS - Application Development System

Enhanced Definition

ADS (Application Development System) is a Fourth Generation Language (4GL) environment primarily associated with the CA IDMS database management system on IBM mainframes. It provides a comprehensive set of tools for rapidly developing online, interactive applications that access and manipulate IDMS data. ADS streamlines application development by abstracting much of the low-level coding typically required in languages like COBOL.

Key Characteristics

- 4GL Environment: Offers a high-level, declarative, and procedural language (ADSO - Application Development System Online) that significantly reduces the amount of code needed compared to traditional 3GLs.
- Integrated with IDMS: Tightly coupled with the CA IDMS database, providing optimized and direct access to its network-model data structures.
- Screen-Oriented Development: Features tools for designing interactive screens (called maps or dialogs) for user input and output, simplifying the creation of user interfaces.
- Online Transaction Processing (OLTP): Specifically designed for building interactive, real-time applications that handle concurrent user requests and database updates efficiently.
- Modular Architecture: Supports the creation of reusable processes and routines to promote modularity and maintainability within applications.
- Runtime Environment: ADS applications execute within the IDMS Central Version (CV) environment, leveraging its transaction management and resource control capabilities.

Use Cases

- Developing interactive data entry and inquiry systems for business operations, such as order processing, inventory management, or customer service.
- Creating online applications that provide real-time access and updates to critical IDMS databases for various enterprise functions.
- Building custom user interfaces and reporting tools for specific departmental needs that rely on IDMS data.
- Modernizing or migrating legacy batch processes into interactive online applications to improve user experience and operational efficiency.

Related Concepts

ADS is inextricably linked to the CA IDMS database management system, serving as its primary native application development environment. It leverages IDMS's data dictionary, database structures, and transaction processing capabilities. While ADS applications are typically self-contained within the IDMS environment, they can sometimes interface with COBOL programs for complex business logic or external system integrations, using CALL statements. JCL (Job Control Language) is used for batch utilities related to IDMS, such as database maintenance, backup/recovery, and the compilation/linking of ADS components, although much of the development is interactive.

Best Practices:

Optimize IDMS DML: Design ADS processes to make efficient use of IDMS Data Manipulation Language (DML) commands, minimizing database I/O and locking contention.
Modularize Applications: Break down complex applications into smaller, reusable routines and processes to enhance maintainability, testing, and code reuse.
Implement Robust Error Handling: Incorporate comprehensive error trapping and recovery mechanisms within ADS processes to gracefully handle database errors, user input issues, and system failures.
Utilize IDMS Security: Leverage IDMS's built-in security features (e.g., sign-on, resource authorization, access keys) in conjunction with ADS application logic to control user access and data integrity.
Performance Tuning: Regularly monitor ADS application performance using IDMS utilities and tune map design, process logic, and database access paths to ensure optimal response times.