java - Adding objects to array list -

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• what nullpointerexception, , how fix it? 12 answers

hello trying add class's objects arraylist objects attributes keep getting null pointers reading values txt file assigning them attributes , put object array list

here code

public class users { scanner scan; bufferedreader reader; maingui gui; login login; string name; string surname; string dob; string address; string town; string number; string position; arraylist<users> allusers = new arraylist<users>();   public users(login login){      this.login = login;   open(); }  public void open(){   try {     url path = users.class.getresource("records.txt");     file f = new file(path.getfile());     reader = new bufferedreader(new filereader(f));     scan = new scanner(reader);     } catch (filenotfoundexception e) {     system.out.println("file not found");     } }  public void readrecords(){  open();  while(scan.hasnext()){      users user = new users(login);      user.name = scan.next();      user.surname = scan.next();      user.dob = scan.next();      user.address = scan.next();      user.address = addspace(user.address);      user.town = scan.next();      user.number = scan.next();      user.position = scan.next();      allusers.add(user);  }  scan.close();  }   public void printusers(){    readrecords();      for(users user : allusers){      system.out.println("" + user );    }    }  } 

i have included methods playing part in in order me better.

change part of code, need set values in user object creating.

users user = new users(login); user.name = scan.next(); .. allusers.add(user); 

and better create getter , setters attributes.

and don't need set values null in constructor, java you.