JAVA

Using the class Person defined below create a class Friends that manages a list of Person. This class should have the following methods:

add(Person p) add new person to set;

search(Person p) returns true if p is a member of the set of friends, false otherwise;

size() returns number of friends

getSurname(String s) returns a set of just those persons whose surname is s;

getFirstname(String f) - returns a set of just those persons whose surname is f;

getFreq(String f) returns number of persons whose first name is f;

del(Person p) remove person p if present;

sort() returns a sorted list of Person.

You may use a ArrayList or a LinkedList for your collection of Person. Please full working implementation with the main method that prints results of all methods.

final class Person implements Comparable{

private final String sName;

private final String fName;

Person(String fn, String sn){fName = fn; sName = sn;}

public String sName(){return sName;}

public String fName(){return fName;}

public String toString(){return fName+" "+sName;}

public boolean equals(Object ob){

if(!(ob instanceof Person)) return false;

Person p = (Person)ob;

return sName.equals(p.sName) && fName.equals(p.fName);

}

public int compareTo(Person p){

if(p == null) return -1;

if(this.equals(p)) return 0;

return sName.compareTo(p.sName);

}

public int hashCode(){

return 41 * sName.hashCode() * fName.hashCode();

}

}