import java.util.IdentityHashMap;

import java.util.HashMap;

import java.util.Map;

public class IdentityHashMapDemo{

public static void main(String[] args){

Map<Employee, String> map1 = new IdentityHashMap<Employee, String>();

Map<Employee, String> map2 = new HashMap<Employee, String>();

Employee e1 = new Employee("John Doe", 28);

map1.put(e1, "SALES");

System.out.println(map1);

Employee e2 = new Employee("Jane Doe", 26);

map2.put(e2, "MGMT");

System.out.println(map2);

System.out.println("map1 contains key e1 = " + map1.containsKey(e1));

System.out.println("map2 contains key e2 = " + map2.containsKey(e2));

e1.setAge(29);

e2.setAge(27);

System.out.println(map1);

System.out.println(map2);

System.out.println("map1 contains key e1 = " + map1.containsKey(e1));

System.out.println("map2 contains key e2 = " + map2.containsKey(e2));

}

}

class Employee{

private String name;

private int age;

Employee(String name, int age){

this.name = name;

this.age = age;

}

public boolean equals(Object o){

if(!(o instanceof Employee)){

return false;

}

Employee emp = (Employee)o;

return this.name.equals(emp.name) && this.age == emp.age;

}

public int hashCode(){

int hashCode = 19;

hashCode = hashCode*31 + this.name.hashCode();

hashCode = hashCode*31 + age;

return hashCode;

}

void setAge(int age){

this.age = age;

}

void setName(String name){

this.name = name;

}

public String toString(){

return this.name + " " + this.age;

}

}