Examine the starter code StudentChooser.java. Replace each ? in the code with the number of students in your class. If you have a very large class, use a subset of all students.

 

There are 10 students 

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/*
* Activity 2.4.1
*/
import java.util.Scanner;

/*
* Collects a user value between 1 and the number of students in your class inclusive and prints
* the corresponding student from an alphabetized String containing those student names, separated
* by a space.
*/
public class StudentChooser
{
 public static void main(String[] args)
 {
   String month = getInput();
   // Display the end result before program termination
   System.out.println("The student you chose was: " + month);
 }
 
 /**
  * Determine whether a given String can be parsed as an integer.
  * @param str a String with unknown contents
  * @return true if str can be parsed as an integer, false otherwise.
  */
 public static boolean isInteger(String str)
 {
   // null references are not integers.
   if (str == null)
   {
     return false;
   }
   
   // an intermediary variable storing the length of str
   // because we will be reusing that value.
   int length = str.length();
   
   // empty strings cannot be parsed as integers
   if (length == 0)
   {
       return false;
   }
   
   // this will count the current position in str
   // begins at index 0
   int i = 0;
   
   // Check for a negative symbol at the beginning of str
   if (str.substring(0, 1).equals("-"))
   {
       // a String that contains just the negative symbol is not an int.
       if (length == 1)
       {
           return false;
       }
       // advance to the first potential digit given a leading negative symbol
       i = 1;
   }
   
   // This loop will terminate if i becomes equal to or greater than length
   while (i < length)
   {
     // characterAtIndex stores the single element substring at position i within str
     String characterAtIndex = str.substring(i, i+1);
     // if any character in str (after a potential leading negative symbol)
     // precedes 0 or exceeds 9, it will be a letter or symbol that cannot
     // represent a digit. These letters or symbols will lead to an str value
     // that cannot be parsed as an int.
     if (characterAtIndex.compareTo("0") < 0 ||
       characterAtIndex.compareTo("9") > 0)
     {
       return false;
     }
     // incrementing the value of i each iteration by one ensures
     // that the loop will terminate when i == length
     i += 1;
   }
   // Having made it past all the conditions that could possibly lead
   // to a value of str that could not be parsed as an int,
   return true;
 }
 
 /**
  * Uses a String containing the students in your class sorted alphabetically and
  * separated by spaces to retreive the student represented by studentNumber
  *
  * @param studentNumber Precondition: studentNumber is an int between 1 and ? inclusive
  * @return the student name corresponding to studentNumber
  */
 public static String getStudent(int studentNumber)
 {

 }
 
 /**
  * Collects user input and calls helper methods to process it.
  * @return
  */
 public static String getInput()
 {
   // Instantiate a Scanner using the standard input (terminal/command line)
   Scanner sc = new Scanner(System.in);
   // Prompt the user for input
   System.out.println("Enter an integer between 1 and ? inclusive: ");
   // The next line typed by a user (terminiating with the enter/return key) is stored as input.
   String input = sc.nextLine();
   
   // The termination condition for this loop is user input that can be parsed as an integer
   // with value between 1 and ? inclusive.
   while (!isInteger(input) || Integer.parseInt(input) > ? || Integer.parseInt(input) < 1)
   {
     // re-prompt the user ot provide the specified kind of input.
     System.out.println("Please enter an integer between 1 and ? inclusive: ");
     // Store a new value for input.
     input = sc.nextLine();
   }
   // Display the user's input
   System.out.println("Your integer was: " + input);
   // returns the value produced by the getStudent method, as determined by the parameter
   // resulting from parsing the user's String input as an Integer.  
   return getStudent(Integer.parseInt(input));
 }
 
}

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2) Complete the getStudent method above using your annotated getMonth method and the comments in StudentChooser.java as a guide.

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Answer o complete the getStudent method you need to provide the implementation that retrieves th... View the full answer