Question

Write the following in Java

Design a class called ReviewSystem, this class should have an attribute reviewList, which is an ArrayList type.

add a constructor to initialize the attribute.

add a method addReviewAndComment(). This method asks from the user to provide an integer (0 to 4 for the five ratings) and a String as a comment. If the user inputs -1, it ends the loop of asking. All valid user inputs should be saved to the reviewList attribute. For example:

Type rating + comments. To end: -1 4 Great place! 4 Loved the food. 1 Pretty bad service. 3 New owners are nice. 0 Yuk!!! 2 What a gem. -1

add a method displayComments(Rating rating). This method displays all comments for a given rating to the console.

add a method displayCommentsUp(Rating rating). This method displays all comments for a given rating and all comments for the ratings better than the given rating. for example, displayCommentsUp(Rating.GOOD) should display all the comments for ratings GOOD, BETTER, and BEST.

create a class ReviewSystemDriver, add a main method to utilize the ReviewSystem class.

Enum

Answer 1

//ReviewSystemDriver.java

package reviewsystem;

public class ReviewSystemDriver {

   public static void main(String args[]) {
       ReviewSystem rs = new ReviewSystem(); //initializing a reviewsystem object
       rs.addReviewAndComment(); //to add to reviewList
       rs.displayComments("GOOD");   //searches for comments with GOOD rating ONLY
       rs.displayCommentsUp("GOOD"); //searches for comments with GOOD rating and ABOVE
   }
  
}

//Rating.java

package reviewsystem;

public class Rating { //a class which stores a Rating
   int star; //how many stars (0-4)
   String comment; //What comment is given
   String rating; //(WORST,WORSE,GOOD,BETTER,BEST) according to the rating(0-4)
   //getter setter methods for class variables
   public String getRating() {
       return rating;
   }
   public void setRating(String rating) {
       this.rating = rating;
   }
   public int getStar() {
       return star;
   }
   public void setStar(int star) {
       this.star = star;
   }
   public String getComment() {
       return comment;
   }
   public void setComment(String comment) {
       this.comment = comment;
   }  
}

//ReviewSystem.java

package reviewsystem;

import java.util.ArrayList;
import java.util.Scanner;

public class ReviewSystem {
   ArrayList<Rating> reviewList = new ArrayList<Rating>(); //list of Rating class
  
   public void addReviewAndComment() { //prompts the user to enter the star and comments
       Scanner i = new Scanner(System.in); //for taking integer input
       Scanner s = new Scanner(System.in); //for taking string input
       System.out.println("Type rating + comment. To end -1: ");
       int put = 0;
       while(put!=-1) {
           Rating r = new Rating(); //Rating class so that we can add it to the ArrayList
           put = i.nextInt();
           if(put == -1) { //if user inputs -1
               break;
           }
           r.setStar(put);
           if(put == 4) {
               r.setRating("BEST"); //setting the Ratings according to the stars
           }
           else if(put == 3) {
               r.setRating("BETTER");
           }
           else if(put == 2) {
               r.setRating("GOOD");
           }
           else if(put == 1) {
               r.setRating("WORSE");
           }

           else if(put == 0) {
               r.setRating("WORST");
           }
           else {
               System.out.println("Some error occured try again!(Rating: 0-4)"); //if invalid input then next loop
               continue;
           }
           r.setComment(s.nextLine()); //takes the comment as input
           reviewList.add(r); //adding the Rating object to the List
       }
   }
   public void displayComments(String str) { //Displays all comments with a particular Rating
       for(int i = 0; i < reviewList.size(); i++) {
           if(reviewList.get(i).getRating().equals(str)) {
               System.out.print("\nStars: "+reviewList.get(i).getStar());
               System.out.print("\nComment: "+reviewList.get(i).getComment()+"\n");
           }
       }
   }
  
   public void displayCommentsUp(String str) { //displays all comments equal and above a particular rating
       int str_int = 0;
       if(str.equals("WORST")) { // we set the rating value to compare later
           str_int = 0;
       }
       else if(str.equals("WORSE")) {
           str_int = 1;
       }
       else if(str.equals("GOOD")) {
           str_int = 2;
       }

       else if(str.equals("BETTER")) {
           str_int = 3;
       }

       else if(str.equals("BEST")) {
           str_int = 4;
       }
       for(int i = 0; i < reviewList.size(); i++) {
           if(reviewList.get(i).getStar() >= str_int) {
               System.out.print("\nStars: "+reviewList.get(i).getStar());
               System.out.print("\nComment: "+reviewList.get(i).getComment()+"\n");
           }
       }
      
   }
  
   public void displayReview() { // to display the arraylist
       for(int i = 0; i< reviewList.size(); i++) {
           System.out.print("\nStars: "+reviewList.get(i).getStar());
           System.out.print("\nComment: "+reviewList.get(i).getComment()+"\n");
       }
   }
}

//ReviewSystemDriver.java

Review System.java Rating.java Review System Driver.java X 1 package reviewsystem; 2 3 public class ReviewSystemDriver { 4 50 public static void main(String args[]) { 6 Reviewsystem rs = new ReviewSystem(); //initializing a reviewsystem object rs.addReviewAnd Comment(); //to add to reviewList 8 rs.displayComments("GOOD"); //searches for comments with GOOD rating ONLY rs.displayCommentsUp("GOOD"); //searches for comments with GOOD rating and ABOVE 10 11 12 } 13 9 }

//Rating.java

//ReviewSystem.java

4 } Review System.java Rating.java X Review System Driver.java 1 package reviewsystem; 2 3 public class Rating { l/a class which stores a Rating int star; //how many stars (0-4) 5 String comment; // What comment is given 6 String rating;' //(WORST , WORSE, GOOD, BETTER, BEST) according to the rating (0-4) 7 //getter setter methods for class variables public String getRating() { 9 return rating; 10 110 public void setRating (String rating) { 12 this.rating = rating; 13 14 public int getStar() { 15 return star; 16 17 public void setStar(int star) { 18 this.star = star; 19 20 public String getComment() { 21 return comment; 22 230 public void setComment(String comment) { 24 this. comment = comment; 25 26 } 27 } } } } w

ReviewSystem.java X Rating.java Review System Driver.java 1 package reviewsystem; 2 3º import java.util.ArrayList; 4 import java.util.Scanner; 5 6 public class Reviewsystem { 7 ArrayList<Rating> reviewList = new ArrayList<Rating>(); //list of Rating class 8 90 public void addReviewAnd Comment() { //prompts the user to enter the star and comments 10 Scanner i = new Scanner(System.in); //for taking integer input 11 Scanner s = new Scanner(System.in); //for taking string input 12 System.out.println("Type rating + comment. To end -1: "); 13 int put = 0; 14 while(put!=-1) { 15 Rating r = new Rating(); //Rating class so that we can add it to the ArrayList 16 put = i.nextInt(); 17 if(put == -1) { //if user inputs -1 18 break; 19 } 20 r.setStar(put); 21 if(put == 4){ 22 r.setRating("BEST"); //setting the Ratings according to the stars 23 24 else if(put == 3) { 25 r.setRating("BETTER"); 26 27 else if(put == 2) { 28 r.setRating("GOOD"); 29 30 else if(put == 1) { 31 r.setRating("WORSE"); 32 } } } }

} } } } ܝܟ Review System.java X Rating.java Review System Driver.java 31 r.setRating("WORSE"); 32 33 34 else if(put == 0) { 35 r.setRating ("WORST"); 36 37 else { 38 System.out.println("Some error occured try again!(Rating: 0-4)"); //if invalid input then next loop 39 continue; 40 41 r.setComment(s.nextLine()); //takes the comment as input 42 reviewList.add(r); //adding the Rating object to the List 43 44 45 public void display Comments (String str) { //Displays all comments with a particular Rating 46 for(int i = 0; i < reviewlist.size(); i++) { 47 if(reviewlist.get(i).getRating().equals(str)) { System.out.print("\nStars: "+reviewList.get(i).getStar()); 49 System.out.print("\nComment: "+reviewlist.get(i).getComment()+"\n"); 50 51 } 52 53 54 public void displayCommentsUp (String str) { //displays all comments equal and above a particular rating 55 int strint = 0; 56 if(str.equals("WORST")) { // we set the rating value to compare later 57 str_int = 0; 58 } 59 else if(str.equals("WORSE")) { 60 str_int = 1; 61 62 else if(str.equals("GOOD")) { 48 } } }

Review System.java * Rating.java Review System Driver.java } else if(str.equals("WORSE")) { str_int = 1; } else if(str.equals("GOOD")) { str_int = 2; } else if(str.equals("BETTER")) { str_int = 3; } else if(str.equals("BEST")) { str_int = 4; } 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 } 89 for(int i = 0; i < reviewList.size(); i++) { if(reviewList.get(i).getStar() >= str_int) { System.out.print("\nStars: "+reviewList.get(i).getStar()); System.out.print("\nComment: "+reviewlist.get(i).getComment()+"\n"); } } } public void displayReview() { // to display the arraylist| for(int i = 0; i< reviewlist.size(); i++) { System.out.print("\nStars: "+reviewlist.get(i).getStar()); System.out.print("\nComment: "+reviewlist.get(i).getComment()+"\n"); } }

//OUTPUT

Review System.java X Rating.java Review System Driver.java 58 } 2. Problems @ Javadoc Declaration & Console X <terminated> Review System Driver (Java Application] C:\Program Files\ava\jre 1.8.0_251\bin\javaw.exe (30-Jul-2020, 3:53:54 am - 3:55:01 am) Type rating + comment. To end -1: 4 It was an Awesome movie 3 Really liked it! 4 OMG! 2 Average.. 2 Okay-ish 1 Not Good Didn't like it -1 Stars: 2 Comment: Average.. Stars: 2 Comment: Okay-ish Stars: 4 Comment: It was an Awesome movie Stars: 3 Comment: Really liked it! Stars: 4 Comment: OMG!

Review System.java X Rating.java ReviewSystem Driver.java 58 } Problems @ Javadoc Declaration & Console X <terminated > Review System Driver (Java Application] C:\Program Files\ava\jre 1.8.0_251\bin\javaw.exe (30-Jul-2020, 3:53:54 am - 3:55:01 am) 2 Average.. 2 Okay-ish 1 Not Good Didn't like it -1 Stars: 2 Comment: Average.. Stars: 2 Comment: Okay-ish Stars: 4 Comment: It was an Awesome movie Stars: 3 Comment: Really liked it! Stars: 4 Comment: OMG ! Stars: 2 Comment: Average.. Stars: 2 Comment: Okay-ish