Help on searching a string array needed!

[scoss04]

Please can someone elp me with this peice of code below, i am trying to get the user to enter a an address, search through the string arrary address, if its found then stop if not found then get them to input data for the rest of the arrays. i can get it to work if i pre set values into the address string
e.g. String [] address = {"rob st","king rd","mary st");
but i need to get the user to enter the data for that too, any help would be great

import java.io.*;
 
public class test4
{
  public static void main(String[] args) throws IOException
  {
 
      final int maxStudents = 10;
    String [] address = new String [maxStudents];
      String [] firstname = new String [maxStudents];
      String[] lastname = new String [maxStudents];
      String [] telno = new String [maxStudents];
      int activeEntries = 0;
        boolean found = false;
    int i = 0;
 
    String addressnosearch = Text.readString("Input name to search for, * to finish");
 
    while ( !addressnosearch.equals("*") )
    {
      found = false;
      i = 0;
 
 
 
 
      while ( !found && i < address.length)
      {
 
        if (address[i].equals(addressnosearch) )  //could use == true
        {
          found = true;
        }
        else
        {
          i++;
        }//end-if
      }//end-while
 
      if (found == true)
      {
        Text.showMessage ( addressnosearch + " was found in the array");
      }
      else
      {
          address[activeEntries] = addressnosearch;
          firstname[activeEntries] =  Text.readString("Enter First Name " );
          lastname[activeEntries] =  Text.readString("Enter Last Name " );
          telno[activeEntries] =  Text.readString("Enter Telephone no " );
          activeEntries = activeEntries + 1;
      }//end-if
         }//end-while
 
    System.exit(0);
 
  }//main
 
}//LinearSearch
 

i get this message after entering an address for
String addressnosearch = Text.readString("Input name to search for, * to finish");

Exception in thread "main" java.lang.NullPointerException
at test4.main(test4.java:31)
Process exited with exit code 1.

[BigDaddyLH]

What is "Text"?

Also this code shows the anti-pattern "object denial":

String [] address = new String [maxStudents];
String [] firstname = new String [maxStudents];
String[] lastname = new String [maxStudents];
String [] telno = new String [maxStudents];

Why not define an Addess class?

[bigbrother]

in line 30:

if (address[i].equals(addressnosearch) ) //could use == true

the variable address[i] is equals to null like all the others locations in the array
address.
to avoid this you can write another if like this

if(address[i]==null) //will not work with .equals!!!
i++;
else if (address[i].equals(addressnosearch) )
found = true;

else
i++;
.
.

hope i've helped
orev hara