package org.jsoup.select;
import org.jsoup.helper.Validate;
import org.jsoup.nodes.Element;
import java.util.Collection;
import java.util.LinkedHashSet;
/**
* CSS-like element selector, that finds elements matching a query.
* <p/>
* <h2>Selector syntax</h2>
* A selector is a chain of simple selectors, separated by combinators. Selectors are case insensitive (including against
* elements, attributes, and attribute values).
* <p/>
* The universal selector (*) is implicit when no element selector is supplied (i.e. {@code *.header} and {@code .header}
* is equivalent).
* <p/>
* <table>
* <tr><th align="left">Pattern</th><th align="left">Matches</th><th align="left">Example</th></tr>
* <tr><td><code>*</code></td><td>any element</td><td><code>*</code></td></tr>
* <tr><td><code>tag</code></td><td>elements with the given tag name</td><td><code>div</code></td></tr>
* <tr><td><code>ns|E</code></td><td>elements of type E in the namespace <i>ns</i></td><td><code>fb|name</code> finds <code><fb:name></code> elements</td></tr>
* <tr><td><code>#id</code></td><td>elements with attribute ID of "id"</td><td><code>div#wrap</code>, <code>#logo</code></td></tr>
* <tr><td><code>.class</code></td><td>elements with a class name of "class"</td><td><code>div.left</code>, <code>.result</code></td></tr>
* <tr><td><code>[attr]</code></td><td>elements with an attribute named "attr" (with any value)</td><td><code>a[href]</code>, <code>[title]</code></td></tr>
* <tr><td><code>[^attrPrefix]</code></td><td>elements with an attribute name starting with "attrPrefix". Use to find elements with HTML5 datasets</td><td><code>[^data-]</code>, <code>div[^data-]</code></td></tr>
* <tr><td><code>[attr=val]</code></td><td>elements with an attribute named "attr", and value equal to "val"</td><td><code>img[width=500]</code>, <code>a[rel=nofollow]</code></td></tr>
* <tr><td><code>[attr^=valPrefix]</code></td><td>elements with an attribute named "attr", and value starting with "valPrefix"</td><td><code>a[href^=http:]</code></code></td></tr>
* <tr><td><code>[attr$=valSuffix]</code></td><td>elements with an attribute named "attr", and value ending with "valSuffix"</td><td><code>img[src$=.png]</code></td></tr>
* <tr><td><code>[attr*=valContaining]</code></td><td>elements with an attribute named "attr", and value containing "valContaining"</td><td><code>a[href*=/search/]</code></td></tr>
* <tr><td><code>[attr~=<em>regex</em>]</code></td><td>elements with an attribute named "attr", and value matching the regular expression</td><td><code>img[src~=(?i)\\.(png|jpe?g)]</code></td></tr>
* <tr><td></td><td>The above may be combined in any order</td><td><code>div.header[title]</code></td></tr>
* <tr><td><td colspan="3"><h3>Combinators</h3></td></tr>
* <tr><td><code>E F</code></td><td>an F element descended from an E element</td><td><code>div a</code>, <code>.logo h1</code></td></tr>
* <tr><td><code>E > F</code></td><td>an F direct child of E</td><td><code>ol > li</code></td></tr>
* <tr><td><code>E + F</code></td><td>an F element immediately preceded by sibling E</td><td><code>li + li</code>, <code>div.head + div</code></td></tr>
* <tr><td><code>E ~ F</code></td><td>an F element preceded by sibling E</td><td><code>h1 ~ p</code></td></tr>
* <tr><td><code>E, F, G</code></td><td>all matching elements E, F, or G</td><td><code>a[href], div, h3</code></td></tr>
* <tr><td><td colspan="3"><h3>Pseudo selectors</h3></td></tr>
* <tr><td><code>:lt(<em>n</em>)</code></td><td>elements whose sibling index is less than <em>n</em></td><td><code>td:lt(3)</code> finds the first 2 cells of each row</td></tr>
* <tr><td><code>:gt(<em>n</em>)</code></td><td>elements whose sibling index is greater than <em>n</em></td><td><code>td:gt(1)</code> finds cells after skipping the first two</td></tr>
* <tr><td><code>:eq(<em>n</em>)</code></td><td>elements whose sibling index is equal to <em>n</em></td><td><code>td:eq(0)</code> finds the first cell of each row</td></tr>
* <tr><td><code>:has(<em>selector</em>)</code></td><td>elements that contains at least one element matching the <em>selector</em></td><td><code>div:has(p)</code> finds divs that contain p elements </td></tr>
* <tr><td><code>:not(<em>selector</em>)</code></td><td>elements that do not match the <em>selector</em>. See also {@link Elements#not(String)}</td><td><code>div:not(.logo)</code> finds all divs that do not have the "logo" class.<br /><code>div:not(:has(div))</code> finds divs that do not contain divs.</code></td></tr>
* <tr><td><code>:contains(<em>text</em>)</code></td><td>elements that contains the specified text. The search is case insensitive. The text may appear in the found element, or any of its descendants.</td><td><code>p:contains(jsoup)</code> finds p elements containing the text "jsoup".</td></tr>
* <tr><td><code>:matches(<em>regex</em>)</code></td><td>elements whose text matches the specified regular expression. The text may appear in the found element, or any of its descendants.</td><td><code>td:matches(\\d+)</code> finds table cells containing digits. <code>div:matches((?i)login)</code> finds divs containing the text, case insensitively.</td></tr>
* <tr><td><code>:containsOwn(<em>text</em>)</code></td><td>elements that directly contains the specified text. The search is case insensitive. The text must appear in the found element, not any of its descendants.</td><td><code>p:containsOwn(jsoup)</code> finds p elements with own text "jsoup".</td></tr>
* <tr><td><code>:matchesOwn(<em>regex</em>)</code></td><td>elements whose own text matches the specified regular expression. The text must appear in the found element, not any of its descendants.</td><td><code>td:matchesOwn(\\d+)</code> finds table cells directly containing digits. <code>div:matchesOwn((?i)login)</code> finds divs containing the text, case insensitively.</td></tr>
* <tr><td></td><td>The above may be combined in any order and with other selectors</td><td><code>.light:contains(name):eq(0)</code></td></tr>
* </table>
*
* @author Jonathan Hedley, jonathan@hedley.net
* @see Element#select(String)
*/
public class Selector {
private final Evaluator evaluator;
private final Element root;
private Selector(String query, Element root) {
Validate.notNull(query);
query = query.trim();
Validate.notEmpty(query);
Validate.notNull(root);
this.evaluator = QueryParser.parse(query);
this.root = root;
}
/**
* Find elements matching selector.
*
* @param query CSS selector
* @param root root element to descend into
* @return matching elements, empty if not
*/
public static Elements select(String query, Element root) {
return new Selector(query, root).select();
}
/**
* Find elements matching selector.
*
* @param query CSS selector
* @param roots root elements to descend into
* @return matching elements, empty if not
*/
public static Elements select(String query, Iterable<Element> roots) {
Validate.notEmpty(query);
Validate.notNull(roots);
LinkedHashSet<Element> elements = new LinkedHashSet<Element>();
for (Element root : roots) {
elements.addAll(select(query, root));
}
return new Elements(elements);
}
private Elements select() {
return Collector.collect(evaluator, root);
}
// exclude set. package open so that Elements can implement .not() selector.
static Elements filterOut(Collection<Element> elements, Collection<Element> outs) {
Elements output = new Elements();
for (Element el : elements) {
boolean found = false;
for (Element out : outs) {
if (el.equals(out)) {
found = true;
break;
}
}
if (!found)
output.add(el);
}
return output;
}
public static class SelectorParseException extends IllegalStateException {
public SelectorParseException(String msg, Object... params) {
super(String.format(msg, params));
}
}
}