The ASF is made up of more than 150 top level projects which cover a wide range of technologies. Chances are if you are looking for a rewarding experience in Open Source, you are going to find it here.
Apache Ambari makes Hadoop cluster provisioning, managing, and monitoring dead simple.
Apache Airavata is a distributed system software framework to manage simple to composite applications with complex execution and workflow patterns on diverse computational resources.
Apache Airavata is a micro-service architecture based software framework for executing and managing computational jobs and workflows on distributed computing resources including local clusters, supercomputers, national grids, academic and commercial clouds. Airavata is dominantly used to build Web-based science gateways and assist to compose, manage, execute, and monitor large scale applications (wrapped as Web services) and workflows composed of these services.
File upload component for Java servlets
The FileUpload component provides a simple yet flexible means of adding support for multipart file upload functionality to servlets and web applications.