Recycling the Programming Environment 66 T feel like I'm writing the same code over and over again," finished goods. The automated warehouse uses a flatbed robot says Benito Prez, a programmer working on a new automated trolley. This robot is a four-wheel electric cart, similar to a golf warehouse design. "I have written so many programs lately that cart except that it has no seats. Flatbed robot trolleys have a flat deal with robotic-type things that control themselves: automated 64 cargo surface about 3 above ground level. These trolleys mailroom trolleys, building surveillance robots, automatic pool have a radio communications device that provides a real-time cleaners, automatic lawn mowers, monorail trains, and now data link to a central warehouse computer. Flatbed trolleys have warehouse trolleys. They are all variations on a theme." two sensors: a path sensor that detects a special type of paint and Lisa Bernoulli, the project manager, has heard this sort of a motion sensor that detects movement. These trolleys follow complaint for years. She replies, "Oh, come on, Ben. These things painted paths around the factory floor. Special paint codes mark aren't really that close. How can you compare a mailroom robot, forks and branches in the paths, trolley start and stop points, and an automated warehouse, and a monorail train? I'll bet less than general location points. 10 percent of the code is the same." The facility includes three loading dock stations and 10 work"Look," says Benito. "All three involve machines that have stations. Each station has a desktop computer connected to the to find a starting point, follow a circuitous route, make stops for central computer. When products are needed or are ready to be loading and unloading, and eventually go to a stopping point. All collected from a workstation, the central computer is informed by three have to make decisions at branches in their routes. All three the worker at the station. The central computer then dispatches have to avoid colliding with things. I'm tired of redesigning code trolleys accordingly. Each station has a drop point and a pickup that is largely familiar to me." point. Flatbed trolleys move about the factory picking up work at "Hmmm," Lisa muses as she looks over the basic require- pickup points and dropping off work at drop points. The program ments for the warehouse system and remembers the monorail that will run the trolleys must interact heavily with the existing system she and Benito had worked on last year. The require- job-scheduling program that helps schedule workstation tasks. ments regarded a small-lot electronics manufacturing firm that How should Lisa go about reusing Benito Prez's work on the was automating its warehouse and product movement system. monorail in their current task of creating a trolley object? Explain The warehouse contains incoming parts, work in progress, and in two paragraphs