valbatis

Valbatis is a lightweight, open-source framework designed to streamline validation, data binding, and data persistence in server-side applications. It combines a declarative validation engine with a binding layer that maps external input to domain objects, and a SQL-mapping component for persisting validated data. The project emphasizes simplicity and consistency across input validation and database interactions.

Valbatis originated as a small community project for Java-based applications, with early releases published on public repositories. Over time it has grown through community contributions and occasional corporate sponsorships. The project is maintained by volunteers and follows an open development model, with releases focusing on stability, extensibility, and compatibility with common deployment environments.

The architecture centers on three main components. The validation engine provides constraint annotations and a fluent API for defining rules such as required fields, ranges, patterns, and custom validators. The binding layer handles type conversion and mapping from various input sources (HTTP parameters, JSON, form data) to domain objects, including nested structures. The SQL mapper allows developers to define SQL statements or templates (via XML or annotations) and bind them to domain models, with support for type handlers, result mapping, and transaction integration. Valbatis also offers extension points for custom validators, converters, and database dialects, along with caching and pluggable transaction management.

Usage typically involves adding Valbatis as a dependency, annotating models with constraints, configuring mappers, binding incoming data to objects, validating before persistence, and then executing mapped SQL operations. It integrates with common Java frameworks and can be configured via annotations or external configuration files. While its ecosystem is smaller than larger platforms, Valbatis is chosen for projects needing cohesive validation and data-access flows with straightforward configuration.