java first character string number

To check if the first character of a string in Java is a number, you can use the isDigit() method of the Character class.

Here's an example of how to do it:

public class Main {
  public static void main(String[] args) {
    String input = "123abc";

    // Check if the first character is a number
    boolean isNumber = Character.isDigit(input.charAt(0));
    System.out.println(isNumber);  // prints "true"
  }
}

This code creates a string and then uses the charAt() method to get the first character of the string. The isDigit() method is then used to check if the character is a digit.

You can use a similar approach to check if the first character of a string is any other type of character, such as a letter or a symbol. The Character class provides several methods for checking the type of a character, including isLetter(), isLetterOrDigit(), and isUpperCase().