Jsoup

Use selector-syntax to find elements

Problem

You want to find or manipulate elements using a CSS or jquery-like selector syntax.

Solution

Use the Element.select(String selector) and Elements.select(String selector) methods:

File input =newFile("/tmp/input.html"); Document doc =Jsoup.parse(input,"UTF-8","http://example.com/"); Elements links = doc.select("a[href]");// a with href Elements pngs = doc.select("img[src$=.png]");   // img with src ending .png Element masthead = doc.select("div.masthead").first();   // div with class=masthead Elements resultLinks = doc.select("h3.r > a");// direct a after h3

Description

jsoup elements support a CSS (or jquery) like selector syntax to find matching elements, that allows very powerful and robust queries.

The select method is available in a Document, Element, or in Elements. It is contextual, so you can filter by selecting from a specific element, or by chaining select calls.

Select returns a list of Elements (as Elements), which provides a range of methods to extract and manipulate the results.

Selector overview

  • tagname: find elements by tag, e.g. a
  • ns|tag: find elements by tag in a namespace, e.g. fb|name finds <fb:name> elements
  • #id: find elements by ID, e.g. #logo
  • .class: find elements by class name, e.g. .masthead
  • [attribute]: elements with attribute, e.g. [href]
  • [^attr]: elements with an attribute name prefix, e.g. [^data-] finds elements with HTML5 dataset attributes
  • [attr=value]: elements with attribute value, e.g. [width=500]
  • [attr^=value], [attr$=value], [attr*=value]: elements with attributes that start with, end with, or contain the value, e.g. [href*=/path/]
  • [attr~=regex]: elements with attribute values that match the regular expression; e.g. img[src~=(?i)\.(png|jpe?g)]
  • *: all elements, e.g. *

Selector combinations

  • el#id: elements with ID, e.g. div#logo
  • el.class: elements with class, e.g. div.masthead
  • el[attr]: elements with attribute, e.g. a[href]
  • Any combination, e.g. a[href].highlight
  • ancestor child: child elements that descend from ancestor, e.g. .body p finds p elements anywhere under a block with class "body"
  • parent > child: child elements that descend directly from parent, e.g. div.content > p finds p elements; and body > * finds the direct children of the body tag
  • siblingA + siblingB: finds sibling B element immediately preceded by sibling A, e.g. div.head + div
  • siblingA ~ siblingX: finds sibling X element preceded by sibling A, e.g. h1 ~ p
  • el, el, el: group multiple selectors, find unique elements that match any of the selectors; e.g. div.masthead, div.logo

Pseudo selectors

  • :lt(n): find elements whose sibling index (i.e. its position in the DOM tree relative to its parent) is less than n; e.g. td:lt(3)
  • :gt(n): find elements whose sibling index is greater than n; e.g. div p:gt(2)
  • :eq(n): find elements whose sibling index is equal to n; e.g. form input:eq(1)
  • :has(seletor): find elements that contain elements matching the selector; e.g. div:has(p)
  • :not(selector): find elements that do not match the selector; e.g. div:not(.logo)
  • :contains(text): find elements that contain the given text. The search is case-insensitive; e.g. p:contains(jsoup)
  • :containsOwn(text): find elements that directly contain the given text
  • :matches(regex): find elements whose text matches the specified regular expression; e.g. div:matches((?i)login)
  • :matchesOwn(regex): find elements whose own text matches the specified regular expression
  • Note that the above indexed pseudo-selectors are 0-based, that is, the first element is at index 0, the second at 1, etc

See the Selector API reference for the full supported list and details.

 

http://jsoup.org/cookbook/extracting-data/selector-syntax

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