【转】解析Html页面:HTML Parser的试用
转自：http://blog.csdn.net/scud/article/details/451397
package com.jscud.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.tags.LinkTag;import org.htmlparser.util.NodeList;import org.htmlparser.util.ParserException;import org.htmlparser.visitors.HtmlPage;import org.htmlparser.visitors.TextExtractingVisitor;import com.jscud.util.LogMan; //一个日志记录类/** * 演示了Html Parse的应用. * * @author scud http://www.jscud.com */public class ParseHtmlTest{ public static void main(String[] args) throws Exception { String aFile = "e:/jscud/temp/test.htm"; String content = readTextFile(aFile, "GBK"); test1(content); System.out.println("===================================="); test2(content); System.out.println("===================================="); test3(content); System.out.println("===================================="); test4(content); System.out.println("===================================="); test5(aFile); System.out.println("===================================="); //访问外部资源,相对慢 test5("http://www.jscud.com"); 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.getTitle(); 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); } /** * 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; } }}