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Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: Double a = 20.5; // 1 occurs double b = a; // 2 occurs   1   : [1]   2   : [2]

Fill in the blanks to implement the toString method. public class Flag {    private double height;    private double width;    private String color;    public 1 toString( 2 ) {       3    }}   1  :[1]   2  :[2]   3  :[3]

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: Double a = 20.5; // 1 occurs double b = a; // 2 occurs   1   : [1]   2   : [2]

public class Genre {   public Genre() { System.out.println(“GENRE”); }}public class MusicGenre extends Genre {   public MusicGenre() { System.out.println(“MUSIC”); }}public class Rock extends MusicGenre {   public Rock () { super(); System.out.println(“ROCK”); }} Given the class definitions above, what is printed to the console when the following lines of code are executed? Assume the code compiles and runs (i.e. ignore typos). MusicGenre g = new MusicGenre();Rock s = new Rock();

You have files Dessert.java, BlueberryMuffin.java, and a driver class named Driver.java. Fill in the correct visibility modifiers so that the comments in the class BlueberryMuffin and Driver’s main method are upheld. public class Dessert {   1 void eat() { /*compiles*/ }   2 void split() { /*compiles*/ }   3 void purchase() { /*compiles*/ } } —– in a separate file in a different package/directory —– public class BlueberryMuffin extends Dessert {   public void nom() { split(); // doesn’t compile purchase(); // compiles }} —– in a separate file in a different package/directory —– public class Driver { public static void main(String[] args) {        BlueberryMuffin b = new BlueberryMuffin();        b.eat(); // compiles        b.split(); // doesn’t compile        b.purchase(); // doesn’t compile }}   1   : [1]  2   : [2]  3   : [3]

Fill in the blanks to implement the toString method. public class Flag {    private double height;    private double width;    private String color;    public 1 toString( 2 ) {       3    }}   1  :[1]   2  :[2]   3  :[3]

public class Game {   public Game() { System.out.println(“GAME”); }}public class BoardGame extends Game {   public BoardGame () { System.out.println(“BOARDGAME”); }}public class Chess extends BoardGame {   public Chess () { super(); System.out.println(“CHESS”); }} Given the class definitions above, what is printed to the console when the following lines of code are executed? Assume the code compiles and runs (i.e. ignore typos). BoardGame p = new BoardGame();Chess c = new Chess();

You have files Dessert.java, BlueberryMuffin.java, and a driver class named Driver.java. Fill in the correct visibility modifiers so that the comments in the class BlueberryMuffin and Driver’s main method are upheld. public class Dessert {   1 void eat() { /*compiles*/ }   2 void split() { /*compiles*/ }   3 void purchase() { /*compiles*/ } } —– in a separate file in a different package/directory —– public class BlueberryMuffin extends Dessert {   public void nom() { split(); // doesn’t compile purchase(); // compiles }} —– in a separate file in a different package/directory —– public class Driver { public static void main(String[] args) {        BlueberryMuffin b = new BlueberryMuffin();        b.eat(); // compiles        b.split(); // doesn’t compile        b.purchase(); // doesn’t compile }}   1   : [1]  2   : [2]  3   : [3]

public abstract class Landmark { public abstract int countVisitors();} Consider the class shown above. Which of the following class definitions will NOT compile?

Given 3 classes (Tulip, Flower, and Plant), Tulip can inherit from both Flower and Plant with the following syntax: public class Tulip extends Flower, Plant { /* valid class definition */}