package us.codecraft.webmagic.selector;
   
   import java.util.ArrayList;
   import java.util.List;
   
   import org.apache.commons.lang3.StringUtils;
   import org.jsoup.nodes.Element;
   import org.jsoup.select.Elements;
   
  /**
   * Links selector based on jsoup. Use absolute url. <br>
   *
   * @author code4crafter@gmail.com <br>
   * @since 0.7.0
   */
  public class LinksSelector extends BaseElementSelector {
  
      @Override
      public String select(Element element) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public List<String> selectList(Element element) {
          Elements elements = element.select("a");
          List<String> links = new ArrayList<>(elements.size());
          for (Element element0 : elements) {
              if (StringUtils.isNotBlank(element0.baseUri())) {
                  links.add(element0.attr("abs:href"));
              } else {
                  links.add(element0.attr("href"));
              }
          }
          return links;
      }
  
      @Override
      public Element selectElement(Element element) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public List<Element> selectElements(Element element) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public boolean hasAttribute() {
          return true;
      }
  }