package us.codecraft.webmagic.selector;
import org.apache.commons.collections.CollectionUtils;
import org.jsoup.nodes.Element;
import org.jsoup.nodes.Node;
import org.jsoup.nodes.TextNode;
import org.jsoup.select.Elements;
import java.util.ArrayList;
import java.util.List;
/**
* CSS selector. Based on Jsoup.
*
* @author code4crafter@gmail.com <br>
* @since 0.1.0
*/
public class CssSelector extends BaseElementSelector {
private String selectorText;
private String attrName;
public CssSelector(String selectorText) {
this.selectorText = selectorText;
}
public CssSelector(String selectorText, String attrName) {
this.selectorText = selectorText;
this.attrName = attrName;
}
private String getValue(Element element) {
if (attrName == null) {
return element.outerHtml();
} else if ("innerHtml".equalsIgnoreCase(attrName)) {
return element.html();
} else if ("text".equalsIgnoreCase(attrName)) {
return getText(element);
} else if ("allText".equalsIgnoreCase(attrName)) {
return element.text();
} else {
return element.attr(attrName);
}
}
protected String getText(Element element) {
StringBuilder accum = new StringBuilder();
for (Node node : element.childNodes()) {
if (node instanceof TextNode) {
TextNode textNode = (TextNode) node;
accum.append(textNode.text());
}
}
return accum.toString();
}
@Override
public String select(Element element) {
List<Element> elements = selectElements(element);
if (CollectionUtils.isEmpty(elements)) {
return null;
}
return getValue(elements.get(0));
}
@Override
public List<String> selectList(Element doc) {
List<String> strings = new ArrayList<String>();
List<Element> elements = selectElements(doc);
if (CollectionUtils.isNotEmpty(elements)) {
for (Element element : elements) {
String value = getValue(element);
if (value != null) {
strings.add(value);
}
}
}
return strings;
}
@Override
public Element selectElement(Element element) {
Elements elements = element.select(selectorText);
if (CollectionUtils.isNotEmpty(elements)) {
return elements.get(0);
}
return null;
}
@Override
public List<Element> selectElements(Element element) {
return element.select(selectorText);
}
@Override
public boolean hasAttribute() {
return attrName != null;
}
}