Какая нужна проверка?
package com.javarush.task.task22.task2202;
/*
Найти подстроку
*/
public class Solution {
public static void main(String[] args) throws TooShortStringException {
System.out.println(getPartOfString("JavaRush - лучший сервис обучения Java."));
}
public static String getPartOfString(String string) throws TooShortStringException {
if (string.replaceAll("[^ ]", "").length() < 4 || string.isEmpty()) {
throw new TooShortStringException();
}
String[] strings;
int a = string.indexOf(" ");
String newString = string.substring(a);
strings = newString.split(" ");
String end = "";
for (int i = 0; i < 5; i++) {
end += strings[i] + " ";
}
String endtrim = end.trim();
return endtrim;
}
public static class TooShortStringException extends RuntimeException {
}
}