import java.util.*; public class Person { //Attributes of class A private A a; //Attributes of ArrayList of class A private ArrayList list; //Attributes of HashMap of class B private HashMap hm; public void setA(A a) { this.a = a; } public A getA() { return a; } public void setList(ArrayList list) { this.list = list; } public ArrayList getList() { return list; } public void setHm(HashMap hm) { this.hm = hm; } public HashMap getHm() { return hm; } public static void main(String[] args) { Person p = new Person(); //set values setValues(p); //get values printValues(p); } public static void setValues(Person p) { // implementation of attributes of class A A aa = new A(); aa.setUserInfo("AJ"); p.setA(aa); // implementation of attributes of ArrayList of class A ArrayList ll = new ArrayList (); ll.add(aa); p.setList(ll); // implementation of attributes of HashMap of class B HashMap hmm = new HashMap(); B b = new B(); b.setLastName("Anant"); hmm.put((long) 1, b); p.setHm(hmm); } public static void printValues(Person p) { System.out.println("Name = " + p.getA().getName()); ArrayList list1 = p.getList(); for(A a : list1) { System.out.println("Name = " + a.getName()); } HashMap hmm1 = p.getHm(); B b1 = hmm1.get((long) 1); System.out.println("Last Name = " + b1.getLastName()); } } public class A { private String name; public void setName(String name) { this.name = name; } public String getName() { return name; } void setUserInfo(String name) { setName(name); } } public class B { private String lastName; public void setLastName(String lastName) { this.lastName = lastName; } public String getLastName() { return lastName; } }

How to make/use Attributes of Classes