Thread: add new element in array

i need help urgently. i try to add new array element into my array which is cusName[20]. the process is that if the name already exist it wont add otherwise it will add to array cusName[20]. however i got error message java.lang.NullPointerException null. Please help me with the following code


import java.util.*;
public class AddCustomer
{
private String[] cusName;
private int index;

public AddCustomer()
{
index = 5;
cusName = new String [20];

cusName[0]= "Allen";
cusName[1]= "Lisa";
cusName[2]= "Jessica";
cusName[3]= "Nicole";
cusName[4]= "Ken";
}

public void addCustomer()
{
Scanner in = new Scanner (System.in);
System.out.println("Input Customer Name");
String name=in.next();

int k, place, index;
place= -1;
for (k=0; k<cusName.length; k++)
{
if (cusName[k].equalsIgnoreCase(name))
{
System.out.println("Sorrry customer name " + name +" already exists");
}

}
if (place == -1)
{
for (index=0; index<cusName.length; index++)
{
cusName[index]=name;

}
//System.out.println(cusName[index]);
}
}
}

i got error message java.lang.NullPointerException null

Please post the full text of the error message. Your edited version leaves out the source line number.
Look at the error message, find the line number where the error occurs and then look at that line in the source and find what variable on that line has a null value. Backtrack in your code to find why that variable does not have a valid value.

You can basically also do as well

/* only for testing */

public class main{

public static void main (String[] args){

int array[]= {2, 5, 7, 8, 9}

System.out.println(array[2]);


}

}

Another tip is to look at each controlling variable in turn, and check where it is being initialized, changed and used.

Do that with k, place and index, for example.

;-)