Scala 和 HTML 解析
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【中文标题】Scala 和 HTML 解析【英文标题】：Scala and HTML parsing 【发布时间】：2010-12-14 07:58:28 【问题描述】：如何将 html DOM 文档加载到 Scala 中？ XML 单例在尝试加载 xmlns 标记时出错。
import java.net._
import java.io._
import scala.xml._
object NetParse
import java.net.URLConnection, URL
import scala.xml._
def netParse(sUrl: String): Elem =
var url = new URL(sUrl)
var connect = url.openConnection
XML.load(connect.getInputStream)
终于找到了解决办法！ - 需要 scala 2.7.7 或更高版本才能工作（2.7.0 有一个致命错误）： How-to-use-TagSoup-with-Scala-XML
【问题讨论】：
【参考方案1】：这可能对您有所帮助 Processing real world HTML as if it were XML in scala
【讨论】：
今天查看该页面，大部分代码示例都丢失了。这是一个仍然包含所有原始内容的版本的链接：web.archive.org/web/20111121010724/http://www.hars.de/2009/01/… 对于那些正在寻找一种简单的方法将这个库放入您的项目的人，请参阅http://mvnrepository.com/artifact/org.ccil.cowan.tagsoup/tagsoup/1.2.1。【参考方案2】：尝试改用scala.xml.parsing.XhtmlParser。
【讨论】：
值得注意的是，该解决方案不适用于“标签汤”——只有格式良好的 XHTML 才能成功解析。因此，与 scala.xml.XML.load* 相比，它基本上只是添加了标准 HTML 实体并显然保留了 CDATA 块。 （就我而言，这就是我所需要的，所以是的！）【参考方案3】：我刚刚尝试将此答案与 scala 2.8.1 一起使用，并最终使用了以下工作：
http://www.hars.de/2009/01/html-as-xml-in-scala.html
我需要的有趣的一点是：
val parserFactory = new org.ccil.cowan.tagsoup.jaxp.SAXFactoryImpl
val parser = parserFactory.newSAXParser()
val source = new org.xml.sax.InputSource("http://www.scala-lang.org")
val adapter = new scala.xml.parsing.NoBindingFactoryAdapter
adapter.loadXML(source, parser)
【讨论】：
这也适用于我。但是，我希望能够将原始 HTML 转换为输入源，因此可以在val source= 行或 adapter.loadXML 部分中。我试过adapter.loadString("<html>...")，但它在格式错误的内容上失败了。有什么想法吗？【参考方案4】：
Scala 刮刀
我推荐Scala Scraper，它可以让你像这样优雅地解析 HTML：
// Parse elements from files, URLs or plain strings
val browser = JsoupBrowser()
val doc = browser.parseFile("core/src/test/resources/example.html")
val doc2 = browser.get("http://example.com")
val doc3 = browser.parseString("<html><h1>parse me</h1></html>")
// Extract the text inside the element with id "header"
doc >> text("#header")
// Extract the <span> elements inside #menu
val items = doc >> elementList("#menu span")
// From each item, extract all the text inside their <a> elements
items.map(_ >> allText("a"))
示例取自 Scala Scraper 的 readme。
【讨论】：
【参考方案5】：/*
Copyright (c) 2008 Florian Hars, BIK Aschpurwis+Behrens GmbH, Hamburg
Copyright (c) 2002-2008 EPFL, Lausanne, unless otherwise specified.
All rights reserved.
This software was developed by the Programming Methods Laboratory of the
Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.
Permission to use, copy, modify, and distribute this software in source
or binary form for any purpose with or without fee is hereby granted,
provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the EPFL nor the names of its contributors
may be used to endorse or promote products derived from this
software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
package tagsoup
import org.xml.sax.InputSource
import javax.xml.parsers.SAXParser
import org.ccil.cowan.tagsoup.jaxp.SAXFactoryImpl
import scala.xml.parsing.FactoryAdapter
import scala.xml._
class TagSoupFactoryAdapter extends FactoryAdapter
val parserFactory = new SAXFactoryImpl
parserFactory.setNamespaceAware(false)
val emptyElements = Set("area", "base", "br", "col", "hr", "img",
"input", "link", "meta", "param")
/** Tests if an XML element contains text.
* @return true if element named <code>localName</code> contains text.
*/
def nodeContainsText(localName: String) = !(emptyElements contains localName)
/** creates a node.
*/
def createNode(pre:String, label: String, attrs: MetaData,
scpe: NamespaceBinding, children: List[Node] ): Elem =
Elem( pre, label, attrs, scpe, children:_* );
/** creates a text node
*/
def createText( text:String ) =
Text( text );
/** Ignore Processing Instructions
*/
def createProcInstr(target: String, data: String) = Nil
/** load XML document
* @param source
* @return a new XML document object
*/
override def loadXML(source: InputSource) =
val parser: SAXParser = parserFactory.newSAXParser()
scopeStack.push(TopScope)
parser.parse(source, this)
scopeStack.pop
rootElem
How-to-use-TagSoup-with-Scala-XML
【讨论】：
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