Question

Write a program named StringWorks.java that asks the user to input a line of text from the keyboard.   Ask the user if they want their answers case sensitive or not. You output should be

1. the list of words in the sentence including duplicates
2. A sorted list of the words (alphabetically)
3. A sorted list of words listed backwards (where z comes before a)
4. A randomly shuffled list of works
5. the list of words in the sentence alphabetically removing duplicates.

You need to remove punctuation. Use the Character.isLetterOrDigit() method.

Sample output:

Please type in a sentence:

I love java, and Java loves me! That is cool, yes?

Do you want case sensitivity? (y/n):

n

List of words: i love java and java loves me that is cool yes

Sorted alphabetically: and cool i is java java love loves me that yes

Sorted backwards: yes that me loves love java java is i cool and

Shuffled: java that cool is i love and loves me java yes

Without duplicates, sorted alphabetically: and cool i is java love loves me that yes

Answer 1

If you have any problem with the code feel free to comment.

Program

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Scanner;
import java.util.Set;

public class Test {
   public static void main(String[] args) {
       Scanner sc = new Scanner(System.in);// for taking console input
       // taking sentence
       System.out.print("Please type in a sentence: ");
       String str = sc.nextLine();

       // taking sensitivity choice
       System.out.print("Do you want case sensitivity? (y/n): ");
       String ch = sc.nextLine();

       // spliting the sentence into array of words
       String[] words = str.split(" ");
       ArrayList<String> list = new ArrayList<>();

       for (int i = 0; i < words.length; i++) {
           if (ch.equalsIgnoreCase("y")) {
               // replacing all punctuations using regex
               // \\W matches all non words and replaces them with blank
               // list.add(words[i].replaceAll("\\W", "")); another way to replace punctuation
               list.add(removePunctuation(words[i]));
           } else if (ch.equalsIgnoreCase("n")) {// when casesensitivy is not allowed
               list.add(removePunctuation(words[i]).toLowerCase());
           }
       }

       // a. show list of words
       System.out.print("List of words: ");
       for (String i : list) {
           System.out.print(i + " ");
       }
       System.out.println();

       // b. show the list of sorted words
       Collections.sort(list);
       System.out.print("Sorted alphabetically: ");
       for (String i : list) {
           System.out.print(i + " ");
       }
       System.out.println();

       // c. show the list . in reverse
       Collections.reverse(list);
       System.out.print("Sorted backwards: ");
       for (String i : list) {
           System.out.print(i + " ");
       }
       System.out.println();

       // d. shuffle the list
       Collections.shuffle(list);
       System.out.print("Shuffled: ");
       for (String i : list) {
           System.out.print(i + " ");
       }
       System.out.println();

       // e. remove duplicates from the list
       list = removeDuplicates(list);
       Collections.sort(list);
       System.out.print("Without duplicates, sorted alphabetically: ");
       for (String i : list) {
           System.out.print(i + " ");
       }
       System.out.println();

       sc.close();
   }

   private static <T> ArrayList<T> removeDuplicates(ArrayList<T> list) {

       // creating a set
       Set<T> set = new LinkedHashSet<>();
       // adding list elements to the set
       // set doesn't allow duplicate elements
       set.addAll(list);
       // removing all the elements from the list
       list.clear();
       // adding all the elemnets of set to the list
       list.addAll(set);

       return list;
   }
  
   //for removing punctuation
   private static String removePunctuation(String word) {
       if (!Character.isLetterOrDigit(word.charAt(0))) {//checking the begning of the word
           word = word.replace(word.charAt(0), ' ');
       }

       //checking the end of the word
       if (!Character.isLetterOrDigit(word.charAt(word.length() - 1))) {
           word = word.replace(word.charAt(word.length() - 1), ' ');
       }

       return word.trim();

   }
}

Output