how to get first digit of substring in java code example

Example 1: get first 5 characters of string java

firstFourChars = input.substring(0, 4);

Example 2: get first character of string java

var string = "freeCodecamp";

string.charAt(0); // Returns "f"

Example 3: character at index of string java

String str = "Grepper";
char ch = str.charAt(0);
//ch is assigned the value of G

Example 4: how to return the first character in an array from a method java

public String firstElement(String[] array)
{
      if (array.length >= 1)
      {
      return array[0];
      }
      else {
          return "";
      }
}