Вывод верный, че ему не нравится
package com.javarush.task.task19.task1918;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.parser.Parser;
import org.jsoup.select.Elements;
import java.io.*;
/*
Знакомство с тегами
*/
public class Solution {
public static void main(String[] args) throws IOException{
String tag = args[0];
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String fileName = reader.readLine();
BufferedReader bufferedReader = new BufferedReader(new FileReader(fileName));
String str = null;
while ((str = bufferedReader.readLine()) != null) {
Document document = Jsoup.parse(str, "", Parser.xmlParser());
Elements el = document.getElementsByTag(tag);
for (Element elem : el) {
System.out.println(elem);
}
}
bufferedReader.close();
reader.close();
}
}