Create JavaScript tool for defining direction of travel in agricultural fields

I have a client that needs to replace an existing Java Applet with a similar JavaScript solution. We call it the AB Line tool. This project depends on the following project to be completed first: Step 1. Migrate legacy JSP system from Windows to AWS Linux — Migrate Front End Application https://www.freelancer.com/projects/software-architecture/Step-Migrate-legacy-JSP-system/ The purpose of this tool is to allow a user to define a line, called an AB Line, indicating the direction of travel, and entry point for chemical sprayers in agricultural fields. There is a servlet responsible for providing vector and meta data in XML format, and another that accepts the output of the tool as query string parameters. We don't expect the tool to be an exact duplicate of the applet, but of course we want it to have the same or better user experience and functionality. Following is a brief overview of the feature set, and I have a more detailed requirement available as well. Attached, you'll find screen shots and I have screen casts available demonstrating the current applet. There are more details, but generally, we'll need to be able to... * enlarge, reduce, and pan the view of the fields * set start and end points for the AB line * move start and end points for the AB line * reset the view so all fields fit the view * select a field and show its AB Line * Clear AB Line from view * Apply changes to AB Line