input buffer while creating multiple objects using for loop in java

Question

I want to create multiple objects using for loop in java but this code is not showing proper output, I can take all inputs properly but output is not shown by the program for the input taken for arr[i].model=sc.nextLine();. And the program is showing "Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException" error. I think it's an input buffer problem. How do I solve it?

    import java.util.Scanner;
    class Object{
    String company;
    String model;
    int price;
    int wheels;
    int headlights;
    int a=10;
    }


    public class Main
    {
    public static void main(String[] args) {
    Scanner sc= new Scanner(System.in);
    int i;
    System.out.println("Enter the number of objects you want 
    to create:");
    int n;
    n=sc.nextInt();
    System.out.println("Enter the input for each object  ");
    
    Object arr[] = new Object[n]; //Here Object is the 
    datatype of arr[] and by using this line of code I am 
    initializing the array arr[]

    for (i=0; i<n; i++){
    System.out.println("Enter the details for the new 
    vehicle");
    arr[i] = new Object();
    arr[i].company=sc.nextLine();
    arr[i].model=sc.nextLine();

    sc.nextLine(); //By writing this line I can take input 
    properly but output is not shown for the previous line of code.

    arr[i].price= sc.nextInt();
    arr[i].wheels=sc.nextInt();
    arr[i].headlights=sc.nextInt();
    }

    System.out.println();

    for(i=0;i<10;i++){
    System.out.println(arr[i].company);
    System.out.println(arr[i].model);
    System.out.println(arr[i].price);
    System.out.println(arr[i].wheels);
    System.out.println(arr[i].headlights);


    }
    }
    }

what did you give as the input of n? – devReddit Jul 17 '21 at 06:23 — devReddit, Jul 17 '21 at 06:23

score 1 · Accepted Answer · answered Jul 17 '21 at 06:25

Below is modified the first for loop which works fine for you requirement

        for (i = 0; i < n; i++) {
        System.out.println("Enter the details for the new vehicle");
        arr[i] = new Object();
        sc.nextLine(); // Add scanner here
        arr[i].company = sc.nextLine();
        //sc.nextLine(); // remove scanner here
        arr[i].model = sc.nextLine();
        arr[i].price = sc.nextInt();
        arr[i].wheels = sc.nextInt();
        arr[i].headlights = sc.nextInt();
    }

Also, added two lines of comment shows where to add and remove scanner. And one more thing I suggest is, while your printing the details, don't hard-code the number of cars as 10, as you have already read that value in 'n', use that for looping

for (i = 0; i < n; i++) {
        System.out.println(arr[i].company);
        System.out.println(arr[i].model);
        System.out.println(arr[i].price);
        System.out.println(arr[i].wheels);
        System.out.println(arr[i].headlights);

    }

input buffer while creating multiple objects using for loop in java

1 Answers1