使用HtmlParser抽取页面所有文本数据的方法总结

方法test1应该说是最有效的，避免了出现很多空格。
package test;


import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;

import org.htmlparser.Node;
import org.htmlparser.NodeFilter;
import org.htmlparser.Parser;
import org.htmlparser.filters.NodeClassFilter;
import org.htmlparser.filters.OrFilter;
import org.htmlparser.nodes.TextNode;
import org.htmlparser.parserapplications.StringExtractor;
import org.htmlparser.tags.LinkTag;
import org.htmlparser.util.NodeList;
import org.htmlparser.util.ParserException;
import org.htmlparser.visitors.HtmlPage;
import org.htmlparser.visitors.TextExtractingVisitor;


/**
* 演示了Html Parse的应用.
*/

public class ParseHtmlTest
{

public static void main(String[] args) throws Exception
{
String aFile = "D:\\Eclipse\\workspace\\search\\test001\\content_1349887.htm";

String content = readTextFile(aFile, "GBK");
StringExtractor se;
se = new StringExtractor (aFile);
System.out.println(se.extractStrings(false));

test1(content);
System.out.println("=====Test1==============================");

test2(content);
System.out.println("=====Test2==========================");

test3(content);
System.out.println("=====Test3===============================");

test4(content);
System.out.println("=====Test4===============================");

test5(aFile);
System.out.println("======Test5==============================");

//访问外部资源,相对慢
test5("http://www.medlink.com.cn");
System.out.println("====================================");

}

/**
* 读取文件的方式来分析内容.
* filePath也可以是一个Url.
*
* @param resource 文件/Url
*/
public static void test5(String resource) throws Exception
{
Parser myParser = new Parser(resource);

//设置编码
myParser.setEncoding("GBK");

HtmlPage visitor = new HtmlPage(myParser);

myParser.visitAllNodesWith(visitor);

String textInPage = visitor.getBody().toString();

System.out.println(textInPage);
}

/**
* 按页面方式处理.对一个标准的Html页面,推荐使用此种方式.
*/
public static void test4(String content) throws Exception
{
Parser myParser;
myParser = Parser.createParser(content, "GBK");

HtmlPage visitor = new HtmlPage(myParser);

myParser.visitAllNodesWith(visitor);

String textInPage = visitor.getTitle();

System.out.println(textInPage);
System.out.println("－－－－－－－－－－－－－－－－－－－－");
System.out.println(visitor.getBody());
}

/**
* 利用Visitor模式解析html页面.
*
* 小优点:翻译了<>等符号
* 缺点:好多空格,无法提取link
*
*/
public static void test3(String content) throws Exception
{
Parser myParser;
myParser = Parser.createParser(content, "GBK");

TextExtractingVisitor visitor = new TextExtractingVisitor();

myParser.visitAllNodesWith(visitor);

String textInPage = visitor.getExtractedText();

System.out.println(textInPage);
}

/**
* 得到普通文本和链接的内容.
*
* 使用了过滤条件.
*/
public static void test2(String content) throws ParserException
{
Parser myParser;
NodeList nodeList = null;

myParser = Parser.createParser(content, "GBK");

NodeFilter textFilter = new NodeClassFilter(TextNode.class);
NodeFilter linkFilter = new NodeClassFilter(LinkTag.class);

//暂时不处理 meta
//NodeFilter metaFilter = new NodeClassFilter(MetaTag.class);

OrFilter lastFilter = new OrFilter();
lastFilter.setPredicates(new NodeFilter[] { textFilter, linkFilter });

nodeList = myParser.parse(lastFilter);

Node[] nodes = nodeList.toNodeArray();

for (int i = 0; i < nodes.length; i++)
{
Node anode = (Node) nodes[i];

String line = "";
if (anode instanceof TextNode)
{
TextNode textnode = (TextNode) anode;
line = textnode.toPlainTextString().trim();
//line = textnode.getText();
}
// else if (anode instanceof LinkTag)
// {
// LinkTag linknode = (LinkTag) anode;
//
// line = linknode.getLink();
// //@todo 过滤jsp标签:可以自己实现这个函数
// //line = StringFunc.replace(line, "<%.*%>", "");
// }

if (isTrimEmpty(line))
continue;

System.out.println(line);
}
}

/**
* 解析普通文本节点.
*
* @param content
* @throws ParserException
*/
public static void test1(String content) throws ParserException
{
Parser myParser;
Node[] nodes = null;

myParser = Parser.createParser(content, null);

nodes = myParser.extractAllNodesThatAre(TextNode.class); //exception could be thrown here

for (int i = 0; i < nodes.length; i++)
{
TextNode textnode = (TextNode) nodes[i];
String line = textnode.toPlainTextString().trim();
if (line.equals(""))
continue;
System.out.println(line);
}

}

/**
* 读取一个文件到字符串里.
*
* @param sFileName 文件名
* @param sEncode String
* @return 文件内容
*/
public static String readTextFile(String sFileName, String sEncode)
{
StringBuffer sbStr = new StringBuffer();

try
{
File ff = new File(sFileName);
InputStreamReader read = new InputStreamReader(new FileInputStream(ff),
sEncode);
BufferedReader ins = new BufferedReader(read);

String dataLine = "";
while (null != (dataLine = ins.readLine()))
{
sbStr.append(dataLine);
sbStr.append("\r\n");
}

ins.close();
}
catch (Exception e)
{
// LogMan.error("read Text File Error", e);
}

return sbStr.toString();
}

/**
* 去掉左右空格后字符串是否为空
* @param astr String
* @return boolean
*/
public static boolean isTrimEmpty(String astr)
{
if ((null == astr) || (astr.length() == 0))
{
return true;
}
if (isBlank(astr.trim()))
{
return true;
}
return false;
}

/**
* 字符串是否为空:null或者长度为0.
* @param astr 源字符串.
* @return boolean
*/
public static boolean isBlank(String astr)
{
if ((null == astr) || (astr.length() == 0))
{
return true;
}
else
{
return false;
}
}

}