How to add an object to an ArrayList in Java

Question

I want to add an object to an ArrayList  but each time I add a new object to an ArrayList with 3 attributes  objt name  address  contact   I get an error   import java util ArrayList  import java util Scanner  public class mainClass       public static void main String args              Scanner input   new Scanner System in           System out println  Plz enter Name               String name   input nextLine            System out println  Plz enter Address               String address   input nextLine            System out println  Plz enter ContactNo               String contact   input nextLine              ArrayList lt Data gt  Contacts   new ArrayList lt Data gt             Data objt   new Data            Contacts add objt Data name  address  contact              Here  Data is the class of which I m trying to create an object and pass it to an ArrayList   public class Data            private String name               private String address               private String cell                 public void Data String n  String a  String c                name   n              address   a              cell   c                    public void printData                 System out println  Name tAddress tContactNo                System out println name     t    address     t    cell

User · Accepted Answer

You need to use the new operator when creating the object  Contacts add new Data name  address  contact       Creating a new object and adding it to list - single step   or else  Data objt   new Data name  address  contact      Creating a new object Contacts add objt      Adding it to the list   and your constructor shouldn t contain void  Else it becomes a method in your class   public Data String n  String a  String c       Constructor has the same name as the class and no return type as such

User · Answer

Contacts add objt Data name  address  contact      This is not a perfect way to call a constructor  The constructor is called at the time of object creation automatically  If there is no constructor java class creates its own constructor   The correct way is      object creation   Data object1   new Data name  address  contact             adding Data object to ArrayList object Contacts  Contacts add object1

User · Answer

change Date to Object which is between parenthesis

User · Answer

You have to use new operator here to instantiate  For example   Contacts add new Data name  address  contact

User · Answer

Try this one   Data objt   new Data name  address  contact   Contacts add objt

[java] How to add an object to an ArrayList in Java

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