Week 8 (Mar 10)

Your "reading" for this week is to prepare for the exam. Begin by taking the sample exam on your own so you know what you need to study.

Sample Questions

Take the exam below on your own, closed book, without a computer. Set a 50-minute timer so you can practice finishing in the time alloted. The actual exam will be similar in difficulty and length to this exam.

exam2_sample.pdf

• These specific questions should not be construed as a study guide. The questions do not necessarily provide information about what you should and/or shouldn't study. Try to write and answer different variants of each question. You may discuss your questions and answers with other students enrolled in the course.

• The answers to sample exams will not be made available. Of course, you can easily check your answers to many questions by editing, compiling, and/or executing the code. This is to help you avoid focusing too much attention on the specifics of these questions.

Tip

Practice drawing memory diagrams for Question 2 (EarRing, LipRing, NavelRing, and NoseRing) of the sample exam.

Memory Diagrams

Activity 9 and the Memory Diagrams tutorial may be helpful for reviewing the basics. For more practice, draw a memory diagram for each of the exercises below.

Exercise 1: Variables

long money = 50;
boolean good = true;
double price = money;
char hash = '#';
String rating = "PG";

Exercise 2: Arrays

int[] data = null;
int[] counts = {10, 3, 7, -5};
double[] scores = new double[3];
String[] words = new String[2];
String[] take = {"CS 159", "CS 227"};

int[] easy = {1, 2, 3};
int[] copy = easy;

Exercise 3: Methods

public static void main(String[] args) {
    int[] nums = {159, 227};
    printArray(nums);
}

public static void printArray(int[] a) {
    System.out.print("{" + a[0]);
    for (int i = 1; i < a.length; i++) {
        System.out.print(", " + a[i]);
    }
    System.out.println("}");
}

Exercise 4: Objects

public class Card {

    private int rank;  // 1=Ace, ..., 11=Jack, 12=Queen, 13=King
    private int suit;  // 0=Clubs, 1=Diamonds, 2=Hearts, 3=Spades

    public Card(int rank, int suit) {
        this.rank = rank;
        this.suit = suit;
    }

    public static void main(String[] args) {
        Card c1 = new Card(8, 1);
        Card c2 = new Card(12, 2);
        Card c3 = c1;
        c1 = c2;
    }
}

Exercise 5: Static

public class BankAccount {

    private static final String PREFIX = "1234";
    private static int nextNumber = 1;

    private String number;
    private String owner;
    private double balance;

    public BankAccount(String owner) {
        this.number = PREFIX + String.format("%04d", nextNumber);
        this.owner = owner;
        nextNumber++;
    }

    public static void main(String[] args) {
        BankAccount ba1 = new BankAccount("Stacie");
        BankAccount ba2 = new BankAccount("Trevor");
    }
}

Video 1: Classes

This video by Dr. Weikle was posted before Exam 1 but is also a great review of HW5 topics.

Video 2: Exceptions

Note: This video is from last year. File I/O is not on this year's Exam 2. Feel free to watch the first half, stopping at 4:45. Or watch the entire video if you would like to see next week's topic.