Scala and HTML parsing
How do you load an HTML DOM document into Scala? The XML singleton had errors when trying to load the xmlns tags.
import java.net._
import java.io._
import scala.xml._
object NetParse {
import java.net.{URLConnection, URL}
import scala.x开发者_C百科ml._
def netParse(sUrl: String): Elem = {
var url = new URL(sUrl)
var connect = url.openConnection
XML.load(connect.getInputStream)
}
}
Finally I found a solution! - Requires scala 2.7.7 or higher to work (2.7.0 has a fatal bug): How-to-use-TagSoup-with-Scala-XML
This may help you Processing real world HTML as if it were XML in scala
Try using scala.xml.parsing.XhtmlParser instead.
I have just tried to use this answer with scala 2.8.1 and ended up using the work from:
http://www.hars.de/2009/01/html-as-xml-in-scala.html
The interesting bit that I needed was:
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)
Scala Scraper
I recommend Scala Scraper that lets you parse HTML elegantly like this:
// 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"))
Examples are taken from the Scala Scraper's readme.
/*
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
加载中,请稍侯......
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