Apr 18: Using Iterators

Learning Objectives

After today's class, you should be able to:

• Explain the Iterable interface and how to use an Iterator.
• Apply Set operations to solve problems involving duplicates.
• Build a Map that represents the frequency of words in a string.

Reminders

• By Friday 11pm: Do the Week 13 reading and take Quiz10
• By Friday 11pm: Finish and submit Lab 10: Word Clouds
• By Monday 11pm: Submit HW 9 Part A (5 files, 40 pts)

Lesson Outline

Mini Lecture [25 min]

• java.util.Iterator / java.lang.Iterable
  • How to update a collection using an iterator
• Card.java / Deck.java / Main.java
  • Iterator makes "for each card in deck" possible
• IteratorDemo.java working with collections
  • Manual: while (iter.hasNext()) and iter.next()
  • Automatic: for (variable : iterable)
• Lesson: Implementations (Hash vs Tree)

Finish Lab10 [50 min]

• Lab 10: Word Clouds
• Did the first 33% on Tuesday; finish the other 67% today.