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步骤 2 : 获取元素 步骤 3 : 可运行项目
首先准备 内容，存放在 b.html ，便于后续解析使用。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en-US" xmlns="http://www.w3.org/1999/xhtml" xml:lang=
"en-US">
<head>
<title>The Java™ Tutorials</title>
<meta name="Description" content=
"Tutorials and reference guides for the Java Programming Language" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<style type="text/css">
/*<![CDATA[*/
body {
margin-left:10px;
margin-right:10px;
line-height: 1.5;
FONT-FAMILY: Arial, Helvetica, sans-serif;
font-size: 0.8em;
}
a:link{text-decoration:none; color:#09569d;}
a:visited{text-decoration:none; color: #3a87cf;}
a:hover{text-decoration:underline; }
.header-container {
background-color: #fff;
border-bottom: 1px solid #C1CFDA;
-webkit-box-shadow: 0 2px 2px rgba(117, 163, 231, 0.1);
box-shadow: 0 2px 2px rgba(117, 163, 231, 0.1);
}
.bookwrapper {
width: auto;
margin: auto;
}
.clearfix {
}
.clearfloat {
clear: both;
overflow: auto;
height: 0px;
font-size: 1px;
line-height: 0px;
}
#brandProdName {
width: auto;
height: auto;
}
#logocover {
display: block;
background: transparent url(images/oracle-java-logo.png) 0px 0px no-repeat;
height: 50px;
width: 229px;
float: left;
}
#productName {
font-size: 16px;
position: relative;
top: 19px;
padding-left: 3px;
color: #457798;
white-space: nowrap;
width: 340px;
}
#TopBar_bl {
width: 100%;
height: 60px;
}
#TopBar_br {
width: 100%;
height: 60px;
}
#TopBar_tl {
margin-left: -110px;
margin-right: -100px;
align: left;
height: 60px;
}
#TopBar_tr {
width: 100%;
height: 60px;
}
#TopBar {
min-width:700px;
padding:25px 100px 10px;
margin-bottom:25px;
clear:both;
border-bottom:1px solid #d2dde5;
border-radius: 3px;
background:#efefef; /* Old browsers */
/* IE9 SVG, needs conditional override of 'filter' to 'none' */
background: url(data:image/svg+xml;base64,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);
background: -moz-linear-gradient(top, #ffffff 0%, #e2eff9 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#ffffff), color-stop(100%,#e2eff9)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* IE10+ */
background: linear-gradient(to bottom, #ffffff 0%,#e2eff9 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#e2eff9',GradientType=0 ); /* IE6-8 */
}
#TopBar_left {
line-height: 14px;
position: absolute;
padding-top: 30px;
padding-right: 30px;
padding-left: 30px;
text-align: left;
font: 13px/20px Arial, Helvetica, sans-serif;
font-weight: bold;
font-size: 20px;
color: #333;
}
@media print {
div#TopBar_left {
margin-left: 0;
}
}
@media print {
div#TopBar_right {
display: none;
}
}
#TopBar_right {
line-height: 12px;
float: right;
padding-top: 10px;
padding-right: 30px;
text-align: left;
}
#TopBar_right a {
font-size: 12px;
margin: 3px;
padding: 0;
}
#Footer {
padding-top: 10px;
padding-left: 10px;
margin-right: 10px;
}
.footertext {
font-size: 10px;
font-family: sans-serif;
margin-top: 1px;
}
div#TutBody {
margin: 10px 20em 10px 3em;
}
div.RightBar {
font-family: sans-serif;
float: right;
}
div.RightBar img {
margin: 0 0 1em 0;
}
div.RightBox {
margin: 10px 3em 10px 0;
width: 15em;
border-style: double;
}
div.BlueRightBox {
margin: 10px 3em 10px 0;
width: 15em;
border-style: double;
background:#efefef; /* Old browsers */
/* IE9 SVG, needs conditional override of 'filter' to 'none' */
background: url(data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiA/Pgo8c3ZnIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgdmlld0JveD0iMCAwIDEgMSIgcHJlc2VydmVBc3BlY3RSYXRpbz0ibm9uZSI+CiAgPGxpbmVhckdyYWRpZW50IGlkPSJncmFkLXVjZ2ctZ2VuZXJhdGVkIiBncmFkaWVudFVuaXRzPSJ1c2VyU3BhY2VPblVzZSIgeDE9IjAlIiB5MT0iMCUiIHgyPSIwJSIgeTI9IjEwMCUiPgogICAgPHN0b3Agb2Zmc2V0PSIwJSIgc3RvcC1jb2xvcj0iI2ZmZmZmZiIgc3RvcC1vcGFjaXR5PSIxIi8+CiAgICA8c3RvcCBvZmZzZXQ9IjEwMCUiIHN0b3AtY29sb3I9IiNlMmVmZjkiIHN0b3Atb3BhY2l0eT0iMSIvPgogIDwvbGluZWFyR3JhZGllbnQ+CiAgPHJlY3QgeD0iMCIgeT0iMCIgd2lkdGg9IjEiIGhlaWdodD0iMSIgZmlsbD0idXJsKCNncmFkLXVjZ2ctZ2VuZXJhdGVkKSIgLz4KPC9zdmc+);
background: -moz-linear-gradient(top, #ffffff 0%, #e2eff9 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#ffffff), color-stop(100%,#e2eff9)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #ffffff 0%,#e2eff9 100%); /* IE10+ */
background: linear-gradient(to bottom, #ffffff 0%,#e2eff9 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#e2eff9',GradientType=0 ); /* IE6-8 */
}
div.Pad {
font-size: 80%;
padding: 1em;
}
div.Pad h2 {
text-align: center;
margin: 0;
}
div.Pad div {
display: list-item;
list-style-image: url(images/arrow-right-gray.gif);
margin: 0.3em 1em;
}
ul.BlueArrows {
list-style-image: url(images/ar_dbl_blue.gif);
}
ul.BlueArrows a:visited, ul.BlueArrows a:link {
text-decoration: none;
}
ul.BlueArrows a:hover, ul.BlueArrows a:active {
text-decoration: underline;
}
h1, h2, h3, h4, h5 {
color: #333;
font-family: sans-serif;
}
h1 {
font-weight: bold;
font-size: 20px;
}
h2 {
font-weight: bold;
font-size: 17px;
}
h3 {
font-weight: bold;
font-size: 14px;
}
h4 {
font-size: 15px;
}
h5 {
font-size: 12px;
}
/*]]>*/
</style>
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<body>
<noscript>A browser with JavaScript enabled is required for this
page to operate properly.</noscript>
<div class="header-container">
<div class="bookwrapper clearfix">
<div id="brandProdName">
<div id="logocover"></div>
<div id="productName" >Documentation</div>
</div>
<br class="clearfloat" />
</div>
</div>
<div id="TopBar">
<div id="TopBar_tr">
<div id="TopBar_tl">
<div id="TopBar_br">
<div id="TopBar_bl">
<div id="TopBar_left">The Java™ Tutorials</div>
<div id="TopBar_right">
<script type="text/javascript">
function search() {
var sform = document.getElementById("searchForm");
var srchelem = document.getElementById("searchField");
var srchelemreal = document.getElementById("keywordreal");
var srchval = srchelem.value;
if (srchval.length == 0) {
return false;
}
srchelemreal.value = srchval;
sform.action = "http://docs.oracle.com/apps/search/search.jsp";
sform.method = "get";
sform.target = "_blank";
sform.submit();
}
</script>
<form id="searchForm" onsubmit="return search()">
<input type="hidden" name="category" value="java"/>
<input type="hidden" name="product" value="e25407-01"/>
<input type="hidden" name="q" value="" id="keywordreal"/>
<label for="searchField">
<input type="text" id="searchField" value="Search the online Java Tutorials"
size="30" onclick="this.value='';" />
</label>
<input type="submit" value="Submit" />
</form>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="RightBar"><img src="images/ThinkingDuke.png" width=
"124" height="128" align="middle" alt=
"Duke thinking about what to study" style="margin-top:2px" /><br />
Not sure where to start?<br />
See <a href="tutorialLearningPaths.html">Learning Paths</a>
<div class="BlueRightBox">
<center>
<h2>Tutorial Contents</h2>
</center>
<div>
<center><a href="reallybigindex.html"><img src=
"images/really_big_index_button.gif" width="108" height="22" align=
"middle" alt="really big index button" /></a></center>
</div>
</div>
<div class="RightBox">
<div class="Pad">
<h2>Tutorial Resources</h2>
<div>Last Updated <a href=
"information/history.html">7/19/2016</a></div>
<div><a href="https://blogs.oracle.com/thejavatutorials/">The Java
Tutorials' Blog</a> has news and updates about the Java SE
tutorials.</div>
<div><a href=
"http://www.oracle.com/technetwork/java/javase/java-tutorial-downloads-2005894.html">
Download the latest Java Tutorials bundle</a>.</div>
</div>
</div>
<div class="RightBox">
<div class="Pad">
<h2>In Book Form</h2>
<div><i>The Java Tutorial, Sixth Edition.</i> <a href=
"http://www.amazon.com/The-Java-Tutorial-Course-Edition/dp/0134034082"
target="_blank">Amazon.com</a>.</div>
</div>
</div>
<div class="RightBox">
<div class="Pad">
<h2>Other Resources</h2>
<div><a href="https://docs.oracle.com/javase/8/docs/">Java SE 8
Developer Guides</a></div>
<div><a href="https://docs.oracle.com/javase/8/docs/api">JDK 8 API
Documentation</a></div>
</div>
</div>
<div class="RightBox">
<div class="Pad">
<h2>Oracle Training and Professional Certification</h2>
<div><a href=
"http://education.oracle.com/pls/web_prod-plq-dad/ou_product_category.getFamilyPage?p_family_id=48">
Java Certification and Training</a></div>
<div><a href=
"http://education.oracle.com/pls/web_prod-plq-dad/db_pages.getpage?page_id=3">
Oracle University</a></div>
</div>
</div>
<div class="RightBox">
<div class="Pad">
<h2>Software</h2>
<div>The <a href=
"http://www.oracle.com/technetwork/java/javase/downloads/index.html">
Java Development Kit</a> (JDK)</div>
<!-- <div><a href="https://netbeans.org/">NetBeans IDE</a></div> -->
<!--
<div><a href=
"http://www.oracle.com/technetwork/java/javaee/downloads/index.html">
Java EE SDK</a></div>
-->
</div>
</div>
</div>
<div id="TutBody">
<p style="background-color: rgb(247, 248, 249); border-width: 1px; padding: 10px; font-style: italic; border-style: solid; border-color: rgb(64, 74, 91);">The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.<br/>See <a href="https://www.oracle.com/technetwork/java/javase/jdk-relnotes-index-2162236.html">JDK Release Notes</a> for information about new features, enhancements, and removed or deprecated options for all JDK releases.</p>
<p>The Java Tutorials are practical guides for
programmers who want to use the Java programming language to create
applications. They include hundreds of complete, working examples,
and dozens of lessons. Groups of related lessons are organized into
"trails".</p>
<h2>Trails Covering the Basics</h2>
These trails are available in book form as <i>The Java Tutorial,
Sixth Edition</i>. To buy this book, refer to the box to the right.
<ul class="BlueArrows">
<li><a href="getStarted/index.html">Getting Started</a> — An
introduction to Java technology and lessons on installing Java
development software and using it to create a simple program.</li>
<li><a href="java/index.html">Learning the Java Language</a>
— Lessons describing the essential concepts and features of
the Java Programming Language.</li>
<li><a href="essential/index.html">Essential Java Classes</a>
— Lessons on exceptions, basic input/output, concurrency,
regular expressions, and the platform environment.</li>
<li><a href="collections/index.html">Collections</a> —
Lessons on using and extending the Java Collections Framework.</li>
<li><a href="datetime/index.html">Date-Time APIs</a> — How to
use the <tt>java.time</tt> pages to write date and time code.</li>
<li><a href="deployment/index.html">Deployment</a> — How to
package applications and applets using JAR files, and deploy them
using Java Web Start and Java Plug-in.</li>
<li><a href="extra/certification/index.html">Preparation for Java
Programming Language Certification</a> — List of available
training and tutorial resources.</li>
</ul>
<h2>Creating Graphical User Interfaces</h2>
<ul class="BlueArrows">
<li><a href="uiswing/index.html">Creating a GUI with Swing</a>
— A comprehensive introduction to GUI creation on the Java
platform.</li>
<li><a href="https://docs.oracle.com/javafx/index.html">Creating a
JavaFX GUI</a> — A collection of JavaFX tutorials.</li>
</ul>
<h2>Specialized Trails and Lessons</h2>
<p>These trails and lessons are only available as web pages.</p>
<ul class="BlueArrows">
<li><a href="networking/index.html">Custom Networking</a> —
An introduction to the Java platform's powerful networking
features.</li>
<li><a href="ext/index.html">The Extension Mechanism</a> —
How to make custom APIs available to all applications running on
the Java platform.</li>
<li><a href="extra/fullscreen/index.html">Full-Screen Exclusive
Mode API</a> — How to write applications that more fully
utilize the user's graphics hardware.</li>
<li><a href="extra/generics/index.html">Generics</a> — An
enhancement to the type system that supports operations on objects
of various types while providing compile-time type safety. Note
that this lesson is for advanced users. The <a href=
"java/index.html">Java Language</a> trail contains a <a href=
"java/generics/index.html">Generics</a> lesson that is suitable for
beginners.</li>
<li><a href="i18n/index.html">Internationalization</a> — An
introduction to designing software so that it can be easily adapted
(localized) to various languages and regions.</li>
<li><a href="javabeans/index.html">JavaBeans</a> — The Java
platform's component technology.</li>
<li><a href="jdbc/index.html">JDBC Database Access</a> —
Introduces an API for connectivity between the Java applications
and a wide range of databases and data sources.</li>
<li><a href="jmx/index.html">JMX</a>— Java Management
Extensions provides a standard way of managing resources such as
applications, devices, and services.</li>
<li><a href="jndi/index.html">JNDI</a>— Java Naming and
Directory Interface enables accessing the Naming and Directory
Service such as DNS and LDAP.</li>
<li><a href="jaxp/index.html">JAXP</a> — Introduces the Java
API for XML Processing (JAXP) technology.</li>
<li><a href="jaxb/index.html">JAXB</a> — Introduces the Java
architecture for XML Binding (JAXB) technology.</li>
<li><a href="rmi/index.html">RMI</a> — The Remote Method
Invocation API allows an object to invoke methods of an object
running on another Java Virtual Machine.</li>
<li><a href="reflect/index.html">Reflection</a> — An API that
represents ("reflects") the classes, interfaces, and objects in the
current Java Virtual Machine.</li>
<li><a href="security/index.html">Security</a> — Java
platform features that help protect applications from malicious
software.</li>
<li><a href="sound/index.html">Sound</a> — An API for playing
sound data from applications.</li>
<li><a href="2d/index.html">2D Graphics</a> — How to display
and print 2D graphics in applications.</li>
<li><a href="sdp/index.html">Sockets Direct Protocol</a> —
How to enable the Sockets Direct Protocol to take advantage of
InfiniBand.</li>
</ul>
</div>
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获取元素比较常见的几种方式： 通过id, 标签或者类名称获取。
package cn.how2j.jsoup;
import java.io.File;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
public class Test {
public static void main(String[] args) throws Exception {
File f = new File("b.html");
if(!f.exists())
return;
Document doc = Jsoup.parse(f,"utf-8");
//通过id获取
Element e = doc.getElementById("productName");
System.out.println(e);
//通过标签获取
Elements es;
es = doc.getElementsByTag("a");
show(es);
//通过类名称获取
es = doc.getElementsByClass("RightBox");
show(es);
//通过属性获取
es = doc.getElementsByAttribute("name");
show(es);
}
private static void show(Elements es) {
for (Element e : es) {
System.out.println(e);
}
}
}
在右上角有本知识点对应的可运行项目下载 ,实在自己搞不出来，就下载解压出来比较一下。
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