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POHow to make an array of child objects
 

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  1. POHow to make an array of child objects
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    <p>I have an assignment from my professor and I can't figure out how to properly create an array of objects. None of the classes but the Client class can be changed; the interface can't be changed either. I'm supposed to be able to create an array of objects from several subclasses and be able to access all of the methods.</p> <p>Here is my error report:</p> <pre><code>MathewBorumP5.java:68: error: cannot find symbol revenue = movies[x].calcRevenue(); ^ symbol: method calcRevenue() location: class Movie MathewBorumP5.java:70: error: cannot find symbol movies[x].getYear(), movies[x].calcRevenue(), ^ symbol: method calcRevenue() location: class Movie MathewBorumP5.java:71: error: cannot find symbol movies[x].calcProfit(revenue), movies[x].categor y()); ^ symbol: method calcProfit(double) location: class Movie MathewBorumP5.java:71: error: cannot find symbol movies[x].calcProfit(revenue), movies[x].categor y()); ^ symbol: method category() location: class Movie MathewBorumP5.java:78: error: cannot find symbol totalRevenue = totalRevenue + movies[x].calcRevenue(); ^ symbol: method calcRevenue() location: class Movie MathewBorumP5.java:81: error: cannot find symbol "%.3f million dollars.", Movie[0].getTotalMovies(), tota lRevenue); ^ symbol: variable Movie location: class MathewBorumP5 6 errors </code></pre> <p><strong>My client class:</strong></p> <pre><code>import java.util.Scanner; public class MathewBorumP5 { public static void main(String[] args) { int choice; boolean restart = true; Scanner input = new Scanner(System.in); Movie[] movies = new Movie[6]; movies[0] = new Animated("Beauty and the Beast", "Gary Trousdale", 1991, 10.0, 5.0, 2.0); movies[1] = new Animated("Peter Pan", "Clyde Geronimi", 1953, 2.0, 1.2, .5); movies[2] = new Documentary("Planet Earth", "Alastair Fothergill", 2006, 10, 20, 5); movies[3] = new Documentary("Drain the Ocean", "Steve Nichols", 2009, 9, 2,3); movies[4] = new Drama("The Shawshank Redemption", "Frank Darabont", 1994, 89, 7, 2); movies[5] = new Drama("The Godfather", "Francis Coppola", 1972, 10, 3, 5); do { menu(); System.out.print("Enter a number from 1 - 5: "); choice = input.nextInt(); System.out.print("\n"); switch(choice) { case 1: item1(movies); break; case 2: item2(movies); break; case 3: break; case 4: break; case 5: restart = false; break; default: System.out.print("You didn't enter a number between 1" + " and 5.\n"); break; } } while(restart == true); } public static void menu() { System.out.print("Warren Moore Movie Menu\n"); System.out.print("1. Show the list of movies in the array\n"); System.out.print("2. Display the total number of movies and the total" + " revenues\n"); System.out.print("3. Search movie by title\n"); System.out.print("4. Display movies sorted by profit in decreasing" + " order\n"); System.out.print("5. Exit\n"); } public static void item1(Movie[] movies) { double revenue; System.out.printf("%-26s%-6s%-10s%-9s%-11s\n", "Title", "Year", "Revenue", "Profit", "Category"); for(int x = 0; x &lt;= 6; x++) { revenue = movies[x].calcRevenue(); System.out.printf("%-26s%-6s%-10s%-9s%-11s\n", movies[x].getTitle(), movies[x].getYear(), movies[x].calcRevenue(), movies[x].calcProfit(revenue), movies[x].category()); } } public static void item2(Movie[] movies) { double totalRevenue; for(int x = movies[0].getTotalMovies(); x &gt; 0; x--) { totalRevenue = totalRevenue + movies[x].calcRevenue(); } printf("The total number of moves is %d, and their total revenue is" + "%.3f million dollars.", Movie[0].getTotalMovies(), totalRevenue); } } </code></pre> <p><strong>My Superclass:</strong></p> <pre><code>public class Movie { protected String title; protected String director; protected int year; protected double productionCost; private static int totalMovies = 0; public Movie() { totalMovies++; } public Movie(String newTitle, String newDirector, int newYear, double newCost) { totalMovies++; title = newTitle; director = newDirector; year = newYear; productionCost = newCost; } public int getTotalMovies() { return totalMovies; } public String getTitle() { return title; } public void setTitle(String newTitle) { this.title = title; } public String getDirector() { return director; } public void setDirector(String director) { this.director = director; } public int getYear() { return year; } public void setYear(int year) { this.year = year; } public double getProductionCost() { return productionCost; } public void setProductionCost(double productionCost) { this.productionCost = productionCost; } public String toString() { return ""; } } </code></pre> <p>Class template(all my classes are basically the same):</p> <pre><code>public class Animated extends Movie implements Profitable { private double rate; private double income; public Animated() { super(); } public Animated(String title, String director, int year, double cost, double rate, double income) { super(title, director, year, cost); this.rate = rate; this.income = income; } public double getRate() { return rate; } public void setRate(double rate) { this.rate = rate; } public double getIncome() { return income; } public void setIncome(double income) { this.income = income; } public String category() { return "Animated"; } public double calcRevenue() { return (income * rate); } public double calcProfit(double revenue) { return (revenue - super.productionCost); } public String toString() { return (super.toString() + ""); } } </code></pre> <p><strong>My interface:</strong></p> <pre><code>public interface Profitable { public abstract String category(); public abstract double calcRevenue(); public abstract double calcProfit(double revenue); } </code></pre>
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