1.4 Three calls, in order

Three calls, in order

Unit 1: Meet Greenfoot · Lesson 1.4 Calling a Method · code exercise, graded

A method call is a name, a pair of parentheses, and whatever you put between them. Three of them in a row, and the order is the whole answer.

What to write

  1. Move the crab 4 forward.
  2. Turn it 90 degrees.
  3. Move it 2 more.

act() is called for you once per frame. You are only filling in the body, the same as you would in Greenfoot.

Your code

Press Run to watch your code on the grid. Nothing is recorded by Run, so press it as often as you like. Step goes one frame at a time, which is the view that actually explains what act() does.




What it is checked against


These are the examples you can see. There are also 2 hidden cases with different setups, so printing the answers below as text passes nothing.




Example 1: what we set up


World w = new World(14, 10, 32);
Harness h = new Harness();
w.addObject(h, 1, 1);
h.act();
System.out.println(h.getX() + "," + h.getY() + "," + h.getRotation());


What it should print


5,3,90






Example 2: what we set up


World w = new World(14, 10, 32);
Harness h = new Harness();
w.addObject(h, 0, 0);
h.act();
System.out.println(h.getX() + "," + h.getY() + "," + h.getRotation());


What it should print


4,2,90









  

















  
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