Week 15: Perspectives
  • TBD

Slides

Download Slides

Hand-in

The hand-in for this week consists of a series of questions designed to emulate the style of the two-hour written exam. However, the scope, difficulty, and length of these questions may not reflect those of the actual exam.

While the hand-in can be easily completed using online resources, lecture slides, and the textbook, I recommend attempting it under exam-like conditions for the most authentic experience: work alone, without any reference materials.

Question 1 Write seven Java keywords.

Question 2 What is a class file?

Question 3 What is double buffering?

Question 4 Write the Java comparison operators.

Question 5

  • Write an expression that causes an ArithmeticException.
  • Write an expression that evaluates to NaN.

Question 6 Write a Java program that causes the compiler error:

incompatible types: possible lossy conversion from long to int

Question 7 In the context of StdDraw, what does setXscale and setYscale do?

Question 8 Given:

static double compoundInterest(double principal, double rate, int years) {
    return principal * Math.pow(1 + rate, years);
}

Identify:

  • the method signature.
  • the method name.
  • the formal parameters.
  • the return type.
  • the method body.

Question 9 Given the program:

public class Main {
    public static void main(String[] args) {
        System.out.print("Hello");
        System.out.println("World!");
    }
}

What is printed if you run:

$ javac Main.java
$ java Main.class

Question 10 Write a program that takes an integer and prints the n first digits of pi:

$ java Pi 1
3
$ java Pi 3
3.14
  • Hint: You may use Math.PI
  • Hint: You may assume n is less than 10.

Question 11 Rewrite the code below using while-loop(s):

for (int i = 0, j = 10; i < j; i++, j--) {
    System.out.println(i + " " + j);
}

Question 12 Are all variables within scope?

int sum = 0;
int i = 0;
while (i < 10) {
int tmp = 0;
if (i % 2 == 0){
for (int j = 0; j < 10; j += 2){
tmp -= j;}} else {
    for (int j = 0; j < 10; j += 2){
tmp += j; }}
sum += tmp * j; i++; }