In IntelliJ IDEA, while taking input in an array from console, character of enter key is accepted as an element

Question

I was seeing an example of linear search in an array in Java, and I wrote this code:

import java.util.*;
public class LinearSearch
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        System.out.print("Enter no. of members: ");
        int l=sc.nextInt();
        String[] list=new String[l];
        System.out.println("Enter the members: ");
        for(int i=0;i<l;i++)
            list[i]=sc.nextLine();
        System.out.print("\nEnter the member you want to search for: ");
        String ts=sc.nextLine();
        for(int i=0;i<l;i++)
        {
            if(list[i].equalsIgnoreCase(ts))
            {
                System.out.println("The member is at index " + i);
                break;
            }
            if(i==l-1)
                System.out.println("There is no such member");
        }
    }
}

But while running this code, due to the System.out.println() at the 10th line, the carriage return (of the println() ) is taken as the element at index 0. Further, as I enter more elements, after each element I need to press Enter key to start the next iteration, but with that, the carriage return of the Enter key is taken as input too. This is the output:

Enter no. of members: 5
Enter the members: 
a
b
c

Enter the member you want to search for: e
There is no such member

I did the following to prevent it:

System.out.println("Enter the members: ");
int j=0;
String in="";
while(list[l-1]==null)
{
    in=sc.nextLine();
    if(in.equals(String.valueOf((char)10))) //10 being the ASCII code of carriage return
        continue;
    else
    {
        list[j] = in;
        j++;
    }
}

But this doesn't work, it still takes carriage return as an element. Is there any way to fix this issue ?

see [Scanner is skipping nextLine() after using next() or nextFoo()?](https://stackoverflow.com/q/13102045/16320675) — user16320675, May 23 '22 at 19:00
check this https://stackoverflow.com/questions/7320315/how-to-test-for-blank-line-with-java-scanner whitespace — katyRosale, May 23 '22 at 19:04
So how can I read the string wihtout readng the carriage return ? Putting a Scanner.nextLine() after it will work ? — Shriesh Kumar, May 23 '22 at 19:08
As told by @Yuvaraj R, I tested it in BlueJ and put a Scanner.nextLine() after Scanner.nextInt() and it works. Thank you very much. So will this bug in IntelliJ be fixed in next version ? — Shriesh Kumar, May 24 '22 at 08:09

score 1 · Accepted Answer · answered May 23 '22 at 19:38

1

You need to skip line after nextInt() call as in the answer mentioned by @user16320675 in the comment

But, there is another bug in Intellij IDEA console, refer answer which kind of skips alternative nextLine() input. Hence, your call ends even when you just enter 3 values in this case but your array size is 5.

Refer

Your program is still correct. Just test your code in other terminal instead of IDEA console

answered May 23 '22 at 19:38

Yuvaraj R

107
1
5

I tested it in BlueJ. The code works correctly and by putting a Scanner.nextLine() after the Scanner.nextInt() makes it work perfectly. It really works now. Thank you very much. – Shriesh Kumar May 24 '22 at 08:07
@ShrieshKumar great! and yes it is fixed already and will be available in next version as mentioned in the tracker. Please accept the answer – Yuvaraj R May 24 '22 at 09:40

In IntelliJ IDEA, while taking input in an array from console, character of enter key is accepted as an element

1 Answers1