Characters, Strings and StringBuilder

Three-letter acronyms are common in the business world. For example, in Java you

use the IDE (Integrated Development Environment) in the JDK (Java Development

Kit) to write programs used by the JVM (Java Virtual Machine) that you might

send over a LAN (local area network). Programmers even use the acronym TLA to

stand for three-letter acronym. Write a program that allows a user to enter three

words, and display the appropriate three-letter acronym in all uppercase letters. If

the user enters more than three words, ignore the extra words. Save the file as

ThreeLetterAcronym.java.