Question

Complete the printPalindrome method in the provided Palindrome.java program.

The printPalindrome method accepts a String as a parameter and prints whether the parameter String is a palindrome (i.e., reads the same forwards as it does backwards, for example, "abba" or "racecar").

Make the code case-insensitive, so that words like "Abba" and "Madam" will be considered palindromes.

import java.util.*;

/**
* Determines if a user entered String is a palindrome, which means the String
* is the same forward and reverse. The determination is case-insensitive.
* Spaces and punctuation must match for palindromes.
*
*/
public class Palindrome {

/**
* Starts program
*
* @param args array of command line arguments
*/
public static void main(String[] args) {
printPalindrome("abba");// palindrome
printPalindrome("racecar");// palindrome
printPalindrome("Madam");// palindrome
printPalindrome("!!!Hannah!!!");// palindrome
printPalindrome("! ! ! Hannah ! ! !");// palindrome
printPalindrome("Dot saw I was tod");// palindrome
printPalindrome("Step on no pets");// palindrome
printPalindrome("Step on no pets!"); // NOT
printPalindrome("dog"); // NOT
printPalindrome("Java"); // NOT
printPalindrome("abca"); // NOT
System.out.println("\n*****Read from User*****");
readConsole();
}

/**
* Reads user's console input and prints the results
*/
public static void readConsole() {
Scanner in = new Scanner(System.in);
System.out.print("Enter a word or phrase: ");
String text = in.nextLine();
printPalindrome(text);
}

/**
* Prints whether text is a palindrome
* @param text String to check whether it is a palindrome
*/
public static void printPalindrome(String text) {
System.out.print("\nisPalindrome: \t");
  
//create a String that is the reverse of text
String reverse = "";
  
// if text equals reversed text (remember to ignore case) then print:
System.out.println("\"" + text + "\" is a palindrome");
// otherwise print:
System.out.println("\"" + text + "\" is NOT a palindrome");
  
}

}

Answer 1

import java.util.*;

/**
 * Determines if a user entered String is a palindrome, which means the String
 * is the same forward and reverse. The determination is case-insensitive.
 * Spaces and punctuation must match for palindromes.
 *
 */
public class Palindrome {

    /**
     * Starts program
     *
     * @param args array of command line arguments
     */
    public static void main(String[] args) {
        printPalindrome("abba");// palindrome
        printPalindrome("racecar");// palindrome
        printPalindrome("Madam");// palindrome
        printPalindrome("!!!Hannah!!!");// palindrome
        printPalindrome("! ! ! Hannah ! ! !");// palindrome
        printPalindrome("Dot saw I was tod");// palindrome
        printPalindrome("Step on no pets");// palindrome
        printPalindrome("Step on no pets!"); // NOT
        printPalindrome("dog"); // NOT
        printPalindrome("Java"); // NOT
        printPalindrome("abca"); // NOT
        System.out.println("
*****Read from User*****");
        readConsole();
    }

    /**
     * Reads user's console input and prints the results
     */
    public static void readConsole() {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter a word or phrase: ");
        String text = in.nextLine();
        printPalindrome(text);
    }

    /**
     * Prints whether text is a palindrome
     * @param text String to check whether it is a palindrome
     */
    public static void printPalindrome(String text) {
        System.out.print("
isPalindrome:   ");

        //create a String that is the reverse of text
        text = text.toLowerCase();
        String reverse = "";
        for(int i = 0;i<text.length();i++){
            reverse = text.charAt(i) + reverse;
        }

        // if text equals reversed text (remember to ignore case) then print:
        if(text.equals(reverse))
            System.out.println(""" + text + "" is a palindrome");
        // otherwise print:
        else
            System.out.println(""" + text + "" is NOT a palindrome");
    }


}

isPalindrome:     "abba" is a palindrome

isPalindrome:     "racecar" is a palindrome

isPalindrome:     "madam" is a palindrome

isPalindrome:     "!!!hannah!!!" is a palindrome

isPalindrome:     "! ! ! hannah ! ! !" is a palindrome

isPalindrome:     "dot saw i was tod" is a palindrome

isPalindrome:     "step on no pets" is a palindrome

isPalindrome:     "step on no pets!" is NOT a palindrome

isPalindrome:     "dog" is NOT a palindrome

isPalindrome:     "java" is NOT a palindrome

isPalindrome:     "abca" is NOT a palindrome

*****Read from User*****
Enter a word or phrase: Madam

isPalindrome:     "madam" is a palindrome