Question

Assignment Purpose

The purpose of this lab is to write a well commented java program that demonstrates the use and re-use of methods with input validation.

Instructions

1. It is quite interesting that most of us are likely to be able to read and comprehend words, even if the alphabets of these words are scrambled (two of them) given the fact that the first and last alphabets remain the same. For example,

“I dn'ot gvie a dman for a man taht can olny sepll a wrod one way.” (Mrak Taiwn)

“We aer all moratls, Hamrbee is an immoratl, and tehre is no question abuot it.” (Kevin Unknown)

2. Write a method named scramble that returns a String and takes a String as an argument.
   1. The argument is actually a word (of length 6 or more).
   2. It then constructs a scrambled version of that word, randomly flipping two characters other than the first and last one.
3. Then write the main method in which you would read the word from the user, send it to scramble, and print the scrambled word.
   1. You can use a loop to read multiple words if you like but it is not necessary.
   2. If the length of the entered word is less than 6, you should keep prompting the user to enter a valid word.
4. After writing all the comments, generate a Javadoc and submit it with the java file.

Hint: First generate two random integers in range of the length of the string. Then use substring method to access characters at those locations. Rest is left to your imagination.

Answer 1

Java code:

/**scramble word
* It is quite interesting that most of us are likely to be able to read and comprehend words,
* even if the alphabets of these words are scrambled (two of them) given
* the fact that the first and last alphabets remain the same
*
*/
import java.util.Scanner;

public class ScrambleWord {
   public String scramble(String word) // scramble method definition
   {
       String result;
       StringBuffer buffer = new StringBuffer(word); // create stringbuffer object
       if (word.length() >= 6) // validate the word length greater than 6 or not
       {
           // get the word length and subtract by 3 to avoid last character
           int len = word.length() - 3;
           // generate random number and add by 1 to avoid first character
           int randomnumber = (int) (Math.random() * len) + 1;
           // generate another random number to fetch another one character
           int randomnumber1 = randomnumber + 1;
           // get the first character to swap
           String first = word.substring(randomnumber, (randomnumber + 1));
           // get the second the chracter to swap
           String second = word.substring(randomnumber1, (randomnumber1 + 1));
           // swap the first character
           buffer.setCharAt(randomnumber, second.charAt(0));
           // swap the second character
           buffer.setCharAt(randomnumber1, first.charAt(0));

           result = buffer.toString();

       } else {
           result = "enter valid word";
       }
       return result;
   }

   public static void main(String args[]) {
       ScrambleWord sw = new ScrambleWord();
       String word, scrambleword;
       Scanner ss = new Scanner(System.in);
       System.out.println("Enter word");
       word = ss.next(); // get word from the user
       scrambleword = sw.scramble(word); // call the scramble method
       System.out.println(scrambleword); // print the scramble word

   }
}
Sample outputs:

sample 1:

sample 2:

Note : Read comments for better understanding of the code.

Steps to generate java document ( I used eclipse IDE)

Step 1 − Open eclipse, select the option Project →Generate Javadoc.

Step 2 − Select the javadoc.exe file from the bin folder of java installation directory,
select the destination folder for the generated java doc and select Next.

Step 3 − Type the title of the documentation in the Document title and select the
finish button.

Step 4 − Finally, you can observe the generated doc files in the generated folder.

You can view the document by opening the index.html file with the browser.