As far as I know Java 7 does not receive free public updates anymore. That means the version's relevance is minimal, if not null. Hackerrank should definitely check on this.

import java.util.Scanner;

public class Solution { public static void main(String[] args) { Scanner sc = new Scanner(System.in);

    System.out.println("================================");
    for (int i = 0; i < 3; i++) {
        String s1 = sc.next();
        int x = sc.nextInt();


                    //this line is the key
        System.out.printf("%-15s%03d\n", s1, x);

    }
    System.out.println("================================");
}

}

java 15

public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        int i = scan.nextInt();
        String s1 = scan.next();
        int i1 = scan.nextInt();
        String s2 = scan.next();
        int i2 = scan.nextInt();
        
        System.out.println("================================");
        System.out.printf("%-15s%03d\n",s,i);
        System.out.printf("%-15s%03d\n",s1,i1);
        System.out.printf("%-15s%03d\n",s2,i2);
        System.out.printf("================================");
        
    }

System.out.printf("%-15s%03d\n",s1,x); Here "%-15s", "%03d" everyone's doubt why we are using -15, 03 because in that question had clearly mentioned the excepted output "java" and "100" occupy 15 character spaces. '-' left-align the string in the 15-character field. %s reads the string the s1, and "%03d" %d is used as to read the integer values and occupy 3 digits.0 pad with leading zeros if the number is less than 3 digits. example : 65 is convert into 065

Great exercise for getting comfortable with formatted output in Java! fairplay 24 pro