Eclipse generates an HTTP Status 404 message, indicating that it is unable to find the http://localhost:8080/TemperatureConverterPrj/ URL. This is expected because the application uses two different URLs to call the two conversion routines with arguments.
Eclipse has a built-in browser window that opens when the server is started, but you can use any external browser to enter the URLs.
http://localhost:8080/TemperatureConverterPrj/RestApp1/getCelsius?fahrenheit=212
Eclipse presents a .json file dialog box.
http://localhost:8080/TemperatureConverterPrj/RestApp1/getFahrenheit?celsius=36.8
Depending on your browser, the results are either returned in the browser or you are prompted to save the results to a text file.