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$1.$ Include phone number $($in the format xxx$-$xxx$-$xxxx$)$ in each record

$2.$ No duplicated ID allowed

$3.$ Add method swap$($int id$1,$ int id$2)$ to swap the location of id$1$ and id$2\text{'}$s references in the list

$4.$ Add method modify$($int id$,$ String lastName, String firstName, double GPA, String phone$)$ to modify the id's record. If such id does not exist, add it as a new record into the list

class Student$\{$

private int id;

private String firstName;

private String lastName;

private double gpa;

public Student$($int in$\_$id$,$ String in$\_$fName, String in$\_$lName,

double g$)\{$

id $=$ in$\_$id;

firstName $=$ in$\_$fName;

lastName $=$ in$\_$lName;

gpa $=$ g;

$\}$

public int getID$()\{$return id;$\}$

public String getfName$()\{$return firstName;$\}$

public String getlName$()\{$return lastName;$\}$

public double getGPA$()\{$return gpa;$\}$

$\}$

public class StudentList $\{$

protected int length;

protected int current$\_$pos;

protected Student$[]$ list;

public StudentList$()$

$\{$

list $=$ new Student$[100]$;

length $=0$;

current$\_$pos $=-1$;

$\}$

public StudentList$($int size$)$

$\{$

if$($size$<2)$ size $=100$;

list $=$ new Student$[$size$]$;

length $=0$;

current$\_$pos $=-1$;

$\}$

public void makeEmpty$()$

$\{$

for$($int i$=0$;i$=$list.length;

$\}$

public int lengthIs$()$

$\{$

return length;

$\}$

private int retrieveIndex$($int id$)$

$\{$

boolean found $=$ false;

int current $=0$;

while$(!$found && current