A Java Network Programming Developer designs, implements, and maintains Java applications that are often high-volume and low-latency, required for mission-critical systems. They contribute to all phases of the development lifecycle, writing well-designed, testable, efficient code. They ensure designs are in compliance with specifications, prepare and produce releases of software components. They often work with network protocols such as TCP/IP and UDP, and may also work with multithreading. Their work is critical in creating complex server-client systems, web servers, chat servers, and similar network-based applications. They also troubleshoot and debug to optimize performance.