Admin UI for administration of spring boot applications
Activiti is a light-weight workflow and Business Process Management (BPM) Platform targeted at business people, developers and system admins. Its core is a super-fast and rock-solid BPMN 2 process engine for Java. It's open-source and distributed under the Apache license. Activiti runs in any Java application, on a server, on a cluster or in the cloud. It integrates perfectly with Spring, it is extremely lightweight and based on simple concepts.
Free and open source log management
Blynk is an Internet of Things Platform aimed to simplify building mobile and web applications for the Internet of Things. Easily connect 400+ hardware models like Arduino, ESP8266, ESP32, Raspberry Pi and similar MCUs and drag-n-drop IOT mobile apps for iOS and Android in 5 minutes
an open source solution to application performance monitoring for java server applications
Distributed Java game server, including cluster management server, gateway server, hall server, game logic server, background monitoring server and a running web version of fishing. State machine, behavior tree, A* pathfinding, navigation mesh and other AI tools
Java language server
inspectIT is the leading Open Source APM (Application Performance Management) tool for analyzing your Java (EE) applications.