What will be printed when the following Java code is executed?

What will be printed when the following Java code is executed?

public class Demo {
  public static void main(String[] args) {
    try {
      String s = null;
      System.out.println(s.length());
    } catch (NullPointerException e) {
      System.out.println("Null pointer caught");
    }
  }
}