how to set attributes for array variable in java(OOP), in line 43 why o[0].name doesnt work? -

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how set attributes array variable in java(oop)? attributes of o[] not set within loop, why? im trying set name o[0], o[0].name doesnt work. why happened? setter , getter doesnt work either, can me explain why can not set attributes in o[]?

import java.util.scanner;  public class orders {     private string name;     private double price;     private int quantity;      public void setname(string name){         this.name= name;     }     public string getname(){         return name;     }     public void setprice(double price){         this.price=price;     }     public double getprice(){         return price;     }     public int getquantity(){         return quantity;     }     public void setquantity(int quantity){         this.quantity=quantity;     }      public static void main(string[] args) {         int num = 0;         double sum=0;         scanner sc = new scanner(system.in);         system.out.println("how many rows of order: ");         num = sc.nextint();         orders[] o = new orders[num];          sc.nextline();          for(int = 0;i<=o.length;i++){              system.out.println("the name of product: ");             o[0].name=sc.nextline();             o[i].setname(sc.nextline());             system.out.println("price of product: ");             o[i].setprice(sc.nextdouble());             system.out.println("quantity of product: ");             o[i].setquantity(sc.nextint());         }         for(orders a: o){             system.out.println("name: "+a.getname()+". price: "+a.getprice()             +". quantity :"+a.getquantity());             double totalprice= a.getquantity()*a.getprice();             sum = sum + totalprice;         }          system.out.println("total price: "+sum);     } } 

you need initialize o[i] object before assigning attributes.
loop should terminate before reaching length of array since start iterator form zero. loop should this:

for(int = 0;i<o.length;i++){         o[i] = new orders();         system.out.println("the name of product: ");         string name = sc.nextline();         o[i].setname(name);         system.out.println("price of product: ");         double price = sc.nextdouble();         o[i].setprice(price);         system.out.println("quantity of product: ");         int quantity = sc.nextint();         o[i].setquantity(quantity);         sc.nextline();         system.out.println("moveing next order:");     } 

one more final note have useful names varaibles. extremely helpful when code gets bigger , practice have programmer.
hope code snippet works!