ITEC 120 2019fall asbrennem ibarland

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intro to arrays
acronyms

What is light-amplified stimulated emission radiation? Why, that's a L.A.S.E.R. of course! This abbreviation is called an acronym.

In lecture, we saw arrays-of-doubles. We will apply similar concepts, but using an array-of-Strings.

1. Re-download the latest Object120.java.
2. Write a test-method testAcronymize. It should contain at least two other interesting test cases beyond:

   assertEquals( "S.C.U.B.A.", acronymize( new String[]{"Self", "contained", "underwater", "breathing", "apparatus"} ) );

   (Hint: think along the lines of "An array of size 0, and size 1, and size many.)
3. Write a stub method for acronymize. Make sure it compiles and runs (and fails) your tests.
4. Complete the body for acronymize.
   Think about:
   • What is your “so-far” (accumulator) variable going to be?
     • What is its initial value?
     • How will you update it, each time through the loop?
   • What is your index variable going to be?
     • What is its initial value?
     • How will you update it, each time through the loop?

   Hint: The built-in function Character.toUpperCase('z') returns 'Z'.

5. Submit your file to D2L, as lab07a.

6. Bonus task: Have your main method prompt the user for a sentence, and then print its acronym. Repeat this until the user types "quit" as the sentence.

   Hints:

   • The function nextLine will get an entire line of input (e.g. String sent = Object120.nextLine();).
   • The function split will take a long string, and split it into an array of words: Object120.split("hi there, all.", " ") returns new String[]{"hi", "there,", "all."}.
   • The 2nd argument to split is is what to use as a delimiter: Object120.split("hi there, all.", ",") returns new String[]{"hi there", " all."}. However, multiple delimiters in a row give an empty-string, which is problematic for our acronymize: Object120.split("hi there ", " ") returns new String[]{"hi", "", "", "", "there", ""}.

     To solve the empty-string conundrum: you can either modify acronymize to ignore empty-strings (not a good solution), or call split with the delimiter " +" — which means the delimiter is one-or-more spaces.

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