How to create an array object?(where am I wrong?)

Question

Output window tell :
java.lang.NullPointerException
at Class.main(Class.java:5)
Exception in thread "main"
here is the source code:
public class Class {
public static void main (String s[]){
Book[] theFirst =new Book[3];
theFirst[2].getNum();
theFirst[2].getIsHere();
theFirst[2].out();
theFirst[2].getIsHere();
theFirst[2].in();
theFirst[2].getIsHere();
class Book{
private int num=0;
String bookName,auName,pageNumber;
private boolean isHere =true;
Book(){
num++;
void getNum(){
System.out.println("������������ "+num);
void getIsHere(){
System.out.println("��������? "+isHere);
void out(){
isHere=false;
void in(){
isHere=true;
}

Answer 1

You just allocated the array..but need to create Book Object
Add this line of code, compile and run it...
theFirst[2] = new Book();
Manikandan
Source Code
public class Class {
public static void main (String s[]){
Book[] theFirst =new Book[3];
theFirst[2] = new Book();
theFirst[2].getNum();
theFirst[2].getIsHere();
theFirst[2].out();
theFirst[2].getIsHere();
theFirst[2].in();
theFirst[2].getIsHere();
class Book{
private int num=0;
String bookName,auName,pageNumber;
private boolean isHere =true;
Book(){
num++;
void getNum(){
System.out.println("������������ "+num);
void getIsHere(){
System.out.println("��������? "+isHere);
void out(){
isHere=false;
void in(){
isHere=true;