Question

Write a class StringsAndThings. The class has one instance variable of type String and a constructor with a parameter to initialize the instance variable. The parameter could contain any characters, including letters, digits, spaces, special characters (+, -, $, @,...), and punctuation marks.

Write methods:

• countNonLetters - that will count how many of the characters in the string are not letters. You can use Character's isLetter method.
• moreVowels - which returns true if the String parameter has more vowels than consonants. Otherwise it returns false. Ignore all other characters that are not letters. Add the isVowel method from Lab6 to your class. You can use isLetter from the Character class.
• noDuplicates - which returns a string where each character in the phrase appears exactly once. Consider upper and lower case letters as different letters. Note that spaces and punctuation are also characters. This is a good place to use String's contains method. Hint: Remember if a boolean expression dup is true then !dup is false. Do not use a do-nothing if clause. There are a lot of weird solutions on the Internet. Do not use anything we have not covered. If the string is Mississippi, the return value will be Misp. Hint: it is easier to use substring here than charAt.

Answer 1

class StringsAndThings {
   private String str;

   public StringsAndThings(String aStr) {
       super();
       str = aStr;
   }
   public int countNonLetters() {
       int count=0;
       for(int i=0;i<str.length();i++)
               if(Character.isLetter(str.charAt(i)))
                   count++;
       return str.length()-count;
   }
   public boolean moreVowels() {
       int count=0;
       String s="AEIOUaeiou";
       for(int i=0;i<str.length();i++)
           if(s.contains(str.charAt(i)+""))
               count++;
       int c1=str.length()-count;
       return count>=c1;
   }
   public String noDuplicates() {
       String res="";
      
       for(int i=0;i<str.length();i++)
           if(!res.contains(str.charAt(i)+""))
                   res=res+str.charAt(i);
      
       return res;
   }
}
public class TestStringsAndThings {
       public static void main(String[] args) {
           StringsAndThings sa= new StringsAndThings("Udaay");
           System.out.println(sa.countNonLetters());
           System.out.println(sa.moreVowels());
           System.out.println(sa.noDuplicates());
       }
}