Since WordLookup and LineRenumberer open and close files,
it is not possible to run a demo through a web browser.
You should try these examples by downloading the source files,
creating a new project for each (with just one class), and invoking main
to try out the application.
WordLookup.java source code
all_words.txt scrabble dictionary file
LineNumberer.java source code
potus.txt list of US president names