Problem solution code:
package step1;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class Task {
public static void main(String[] args) {
List<String> bookList=new ArrayList<>();
SAXReader reader = new SAXReader();
try {
Document document = reader.read(new File("src/step1/books.xml"));
Element rootElm = document.getRootElement();
List<Element> elms=rootElm.elements("book");
for(int i=0;i<elms.size();i++){
Element e = elms.get(i);
bookList.add(e.getText()+"---"+e.attributeValue("author"));
}
} catch (DocumentException e) {
e.printStackTrace();
}
for(int i=0;i<bookList.size();i++){
System.out.println(bookList.get(i));
}
}
}