dsa

Driver.java (7794B)

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 package lab3;
 
 import java.util.Scanner;
 
 public class Driver {
     Scanner in = new Scanner(System.in);
     public static void main(String[] args) {
         int menuSelection;
 
         Driver ui = new Driver();
         MyListReferenceBased myList = new MyListReferenceBased();
 
         ui.welcomeMessage();
 
         do {
             menuSelection = ui.menuSelect();
             System.out.println(menuSelection);
 
             switch (menuSelection) {
                 case 1:
                     ui.addObject(myList);
                     break;
                 case 2:
                     ui.removeObject(myList);
                     break;
                 case 3:
                     ui.getObject(myList);
                     break;
                 case 4:
                     ui.removeAll(myList);
                     break;
                 case 5:
                     ui.printList(myList);
                     break;
                 case 6:
                     ui.deleteLargestObject(myList);
                     break;
                 case 7:
                     myList = ui.reverseList(myList);
                     break;
                 case 8:
                     ui.exit();
                     break;
                 case 9:
                     ui.deleteSmallestObject(myList);
                     break;
                 case 10:
                     ui.compareStrings(myList);
                     break;
                 default:
                     System.out.println("Enter a valid selection.");
             }
         }while(menuSelection != 8);
     }
 
     private int menuSelect() {
         System.out.print("Make your menu selection now: ");
         return Integer.parseInt(in.nextLine());
     }
 
     private void addObject(MyListReferenceBased myList) {
         Object userInput;
         int userIndex;
         System.out.println("You are now inserting an item into the list");
         System.out.print("Enter item: ");
         userInput = in.nextLine();
         System.out.println(userInput);
         System.out.print("Enter position to insert item in: ");
         userIndex = Integer.parseInt(in.nextLine());
         System.out.println(userIndex);
         if (userIndex <= myList.size()) {
             myList.add(userIndex, userInput);
             System.out.println("Item " + userInput + " inserted in position " + userIndex + " in the list");
         }
         else {
             System.out.println("Position specified is out of range!");
         }
     }
 
     private void removeObject(MyListReferenceBased myList) {
         int userIndex;
         System.out.print("Enter position to remove item from ");
         userIndex = Integer.parseInt(in.nextLine());
         System.out.println(userIndex);
         if (userIndex <= myList.size()) {
             System.out.println("Item " + myList.get(userIndex) + " removed from position " + userIndex + " in the list");
             myList.remove(userIndex);
         }
         else {
             System.out.println("Position specified is out of range!");
         }
     }
 
     private void getObject(MyListReferenceBased myList) {
         int userIndex;
         System.out.print("Enter position to retrieve item from: ");
         userIndex = Integer.parseInt(in.nextLine());
         System.out.println(userIndex);
         if (userIndex <= myList.size()) {
             System.out.println("Item " + myList.get(userIndex) + " retrieved from position " + userIndex + " in the list");
         }
         else {
             System.out.println("Position specified is out of range!");
         }
     }
 
     private void removeAll(MyListReferenceBased myList) {
         myList.removeAll();
     }
 
     private void printList(MyListReferenceBased myList) {
         if (myList.size() > 0) {
             System.out.println(myList.toString());
         }
         else {
             System.out.println("List is empty.");
         }
     }
 
     private void deleteLargestObject(MyListReferenceBased myList) {
         int largestIndex = 0;
         String largestString = "";
         String currentString;
         if (myList.size() > 0) {
             for (int i = 0; i < myList.size(); i++) {
                 currentString = myList.get(i).toString();
                 if (currentString.compareTo(largestString) > 0 && largestString.compareTo(currentString) < 0 || largestString.equals("")) {
                     largestIndex = i;
                     largestString = myList.get(largestIndex).toString();
                 }
             }
             System.out.println("Largest item " + largestString + " deleted.");
             myList.remove(largestIndex);
         }
         else {
             System.out.println("List empty, nothing to delete!");
         }
     }
 
     private void deleteSmallestObject(MyListReferenceBased myList) {
         int smallestIndex = 0;
         String smallestString = "";
         String currentString;
         if (myList.size() >0) {
             for (int i = 0; i < myList.size(); i++) {
                 currentString = myList.get(i).toString();
                 if (currentString.compareTo(smallestString) < 0 && smallestString.compareTo(currentString) > 0 || smallestString.equals("")) {
                     smallestIndex = i;
                     smallestString = myList.get(smallestIndex).toString();
                 }
             }
             System.out.println("Smallest item " + smallestString + " deleted.");
             myList.remove(smallestIndex);
         }
         else {
             System.out.println("List empty, nothing to delete!");
         }
     }
 
     private void compareStrings(MyListReferenceBased myList) {
         int userIndex, difference;
         String str1, str2;
         System.out.print("Enter index of first string: ");
         userIndex = Integer.parseInt(in.nextLine());
         System.out.println(userIndex);
         str1 = myList.get(userIndex).toString();
         System.out.print("Enter index of second string: ");
         userIndex = Integer.parseInt(in.nextLine());
         System.out.println(userIndex);
         str2 = myList.get(userIndex).toString();
         difference = str1.compareTo(str2);
         System.out.println("The difference between these two strings is " + difference);
     }
 
     private MyListReferenceBased reverseList(MyListReferenceBased myList) {
         MyListReferenceBased tempList = new MyListReferenceBased();
         int listSize = myList.size();
         if (listSize > 0) {
             for (int i = 0; i < listSize;  i++) {
                 tempList.add(i, myList.get(listSize - 1 - i));
             }
 
             //  myList = tempList;
 
             System.out.println("List has been reversed");
             System.out.print("Here is the content: ");
             for (int i = 0; i < listSize; i++) {
                 System.out.print(tempList.get(i) + " ");
             }
             System.out.println();
         }
         else {
             System.out.println("List is empty.. nothing to reverse!");
         }
         return tempList;
 
     }
 
     private void welcomeMessage() {
         System.out.println("Select from the following menu: ");
         System.out.println("    1. Insert item to list");
         System.out.println("    2. Remove item from list");
         System.out.println("    3. Get item from list");
         System.out.println("    4. Clear list");
         System.out.println("    5. Print size and content of list");
         System.out.println("    6. Delete largest item in list");
         System.out.println("    7. Reverse list");
         System.out.println("    8. Exit program");
         System.out.println("    9. Delete smallest item in list (EXTRA)");
         System.out.println("    10. Compare two strings (EXTRA)");
     }
 
     private void exit() {
         System.out.println("Exiting program...Good Bye");
         System.exit(0);
     }
 }