3.1 | Some computer science concept questions: What is a file? What is an operating system? What does a compile do? What does method visibility mean? What is a classpath? What is a wrapper class? What is a hard disk? What is a method? What creates new objects? What does "pass by value" mean? What is a primitive variable? What is an object variable? |
3.2 | Test your understanding of Java with the following: What does pictureObj.show() do? What does soundObj.play() do? What does FileChooser.pickAFile() do? What does turtle1.turnLeft() do? |
3.3 | Test your understanding of Java with the following: What does turtle1.forward() do? What does turtle1.turn(-45) do? What does turtle1.turn(45) do? What does turtle1.penUp() do? What does turtle1.hide() do? |
3.4 | How do you create new objects in Java? How do you create a World object? How do you create a Turtle object? |
3.5 | Which of the following are class methods and which are object methods? How can you tell which are which? |
3.6 | What does this do? System.out.println(new Picture()); |
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3.7 | How many and what kind of variables (primitive or object) are created in the code below? > String fileName = FileChooser.pickAFile(); > Picture p1 = new Picture(fileName); > p1.show(); |
3.8 | How many and what kind of variables (primitive or object) are created in the code below? > World worldObj = new World(); > Turtle turtle1 = new Turtle(worldObj); > turtle1.forward(30); > Turtle turtle2 = new Turtle(worldObj); > turtle2.turnRight(); > turtle2.forward(30); |
3.9 | How many and what kind of variables (primitive or object) are created in the code below? > double cost = 19.20; > double percentOff = 0.4; > double salePrice = cost * (1.0 - percentOff); |
3.10 | We evaluated the expression FileChooser.pickAFile() when we wanted to invoke the method named pickAFile(). But what does this do? Open the FileChooser class and find the method declaration. |
3.11 | Write a method for Turtle to draw a rectangle. Pass in the width and height for the rectangle. |
3.12 | Write a method for Turtle to draw a hexagon. Pass in the length of the sides. |
3.13 | Write a method for Turtle to draw a pentagon. Pass in the length of the sides. |
3.14 | Write a method for Turtle to draw an equilateral triangle. Pass in the length of the sides. |
3.15 | Create a World object and a Turtle object and use the Turtle object to draw a star. |
3.16 | Create a World object and a Turtle object and use the Turtle object to draw an arrow. |
3.17 | Create a World object and a Turtle object and use the Turtle object to draw a pyramid. |
3.18 | Create a World object and a Turtle object and use the Turtle object to draw a flower. |
3.19 | Create a World object and a Turtle object and use the Turtle object to draw a house. |
3.20 | Create a World object and a Turtle object and use the Turtle object to draw your first name. |