Karel 4.1-4.4

• Monday, October 23, 2017: Read Section 4.1-4.3 and do Exercise 3.5 (DiamondBot) with a Choreographer robot.

• Tuesday October 24, 2017: Section 4.2 review (abstract class, override methods).

  • Class: make a robot (team) to create my figure 4.2b ending from the old blog. Then make a robot (team) to pick up my figure 4.2b start.
  • Homework: Read Section 4.4.
    • What is the function of an interface?
    • What does delegation mean in cs?

• Wednesday, October 25, 2017: Section 4.4 (interfaces)

  • Class: review box on page 76 (purpose of interface, no methods in an interface)
  • Class: review box on page 79 (references can point anywhere)
  • Class: “delegation”.
  • Assignment: Forester. The Forester plants trees and bushes. In the robot world, you see a top view of the forest - tall plants are represented by lots of beepers, short plants are represented by few beepers in a pile. Oak trees are tall (7 beepers in a location). Maple trees are medium height (3 beepers), and bushes are only 1 beeper tall but they take up four locations instead of one. 1. Make a Forester interface that has the doPlanting() method. 2. Implement the Forester interface in OakPlanter, MaplePlanter and BushPlanter. 3. Demonstrate with a short program that plants two oak trees 5 squares apart, and a maple next to a bush.

• Thursday, October 26, 2017: Practice for quiz Friday.

  • Create two robot classes: SpeedyMover and DropMover.
    • SpeedyMover moves two steps when told to move one.
    • DropMover drops a beeper and moves when told to move.
  • Create an interface ArmyCaricature that defines the march() and crawl() methods.
    • march(): go three steps
    • crawl(): go one step and drop a beeper
  • Create a DrillSargent class that bosses two ArmyCaricature robots. The drill sargent should have a void bootCamp(ArmyCaricature a, ArmyCaricature b) method that tells a to do three marches and b to do three crawls.
  • Verify that your DrillSargent works by giving it a SpeedyMover and a DropMover.

Quiz 4.1-4.4 on Friday

You should be able to demonstrate the following skills from Sections 4.1-4.4.

• Create a new class (including constructor from memory).
• Instance variables to remember helper robots.
• Abstract class, then concrete implementation to fill in missing parts.
• Interface: create and implement.
• Comparison of abstract class and interface.

Additional Notes

• Read: old notes, still good.

• Android programming has an AbstractCursor class that handles many commom behaviors. Notice that some of the methods are not there, like:

     abstract public String[] getColumnNames();