A strategy that calculates a connection limit for a protocol adapter based on the available JVM memory. It estimates the memory per connection from total memory and a configured factor, then dynamically adjusts limits. Self-contained and reusable for any service needing to cap concurrent connections based on heap.

A generic caching factory for creating and reusing client instances (e.g., AMQP sender links). Supports time-to-live eviction, custom creation and removal logic, and is thread-safe. This pattern is reusable across any system that needs to pool and expire expensive resources.

Loads SQL statements from YAML files with named parameters, supporting dialect-specific overrides (e.g., H2 vs PostgreSQL). Provides a clean abstraction for externalizing SQL from Java code. Reusable for any project needing database-agnostic SQL statement management.

Manages pending MQTT PUBACK messages with configurable timeout per message. Uses a concurrent map and scheduled timer to handle overflows and timeouts. This component is self-contained and can be extracted for any MQTT client or server that needs to track unacknowledged packets.

Implements a chain-of-responsibility pattern for device authentication. A chain of authentication handlers is tried in order; the first one that successfully authenticates wins. This pattern allows composing multiple authentication mechanisms (e.g., X.509, username/password, JWT) flexibly and is reusable for any multi-auth system.