Question

USING JAVA

Consider the following methods:

StringBuilder has a method append(). If we run:

StringBuilder s = new StringBuilder();

s.append("abc");

The text in the StringBuilder is now "abc"

Character has static methods toUpperCase() and to LowerCase(), which convert characters to upper or lower case. If we run Character x = Character.toUpperCase('c');, x is 'C'.

Character also has a static isAlphabetic() method, which returns true if a character is an alphabetic character, otherwise returns false.

You will also need String's charAt() method, which returns the character at a given index in the String. For example, "Godzilla".charAt(1) returns 'o'.

Write an application as follows:

• public static String getNonAlpha() takes a String as parameter, builds a StringBuilder consisting of only the nonalphabetic characters in the String, and returns a String based on the StringBuilder (eg, sb.toString())
• public static String getUpper() takes a String, builds a StringBuilder of the upper case versions of all the alphabetic characters in the String, and returns a String based on the StringBuilder.
• main() asks the user for input (using a Scanner) and prints the results of running the input String through each of these methods.

Answer 1

import java.util.Scanner;

public class SBTester {
   public static void main(String[] args) {
       Scanner sc = new Scanner(System.in);
       System.out.println("Enter sentense");
       String str = sc.nextLine();
       String nonAlpha = getNonAlpha(str);
       String upper = getUpper(str);
       System.out.println("Non Alpha : " + nonAlpha);
       System.out.println("Uppercase : " + upper);
   }

   private static String getUpper(String str) {
       StringBuffer sb = new StringBuffer();
       // looping through the string and appending to string buffer if it is uppercase
       for (int i = 0; i < str.length(); i++) {
           if (Character.isUpperCase(str.charAt(i)))
               sb.append(str.charAt(i));
       }
       return sb.toString();
   }

   private static String getNonAlpha(String str) {
       StringBuffer sb = new StringBuffer();
       // looping through the string and appending to string buffer if it is non alphabetic
       for (int i = 0; i < str.length(); i++) {
           if (!Character.isAlphabetic(str.charAt(i)))
               sb.append(str.charAt(i));
       }
       return sb.toString();
   }
}