Unescape HTML : HTML Parser « Development « Java Tutorial





/*
 * Static String formatting and query routines.
 * Copyright (C) 2001-2005 Stephen Ostermiller
 * http://ostermiller.org/contact.pl?regarding=Java+Utilities
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * See COPYING.TXT for details.
 */


import java.util.HashMap;
import java.util.regex.Pattern;

/**
 * Utilities for String formatting, manipulation, and queries.
 * More information about this class is available from <a target="_top" href=
 * "http://ostermiller.org/utils/StringHelper.html">ostermiller.org</a>.
 *
 * @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
 * @since ostermillerutils 1.00.00
 */
public class StringHelper {
  private static HashMap<String,Integer> htmlEntities = new HashMap<String,Integer>();
  static {
    htmlEntities.put("nbsp", new Integer(160));
    htmlEntities.put("iexcl", new Integer(161));
    htmlEntities.put("cent", new Integer(162));
    htmlEntities.put("pound", new Integer(163));
    htmlEntities.put("curren", new Integer(164));
    htmlEntities.put("yen", new Integer(165));
    htmlEntities.put("brvbar", new Integer(166));
    htmlEntities.put("sect", new Integer(167));
    htmlEntities.put("uml", new Integer(168));
    htmlEntities.put("copy", new Integer(169));
    htmlEntities.put("ordf", new Integer(170));
    htmlEntities.put("laquo", new Integer(171));
    htmlEntities.put("not", new Integer(172));
    htmlEntities.put("shy", new Integer(173));
    htmlEntities.put("reg", new Integer(174));
    htmlEntities.put("macr", new Integer(175));
    htmlEntities.put("deg", new Integer(176));
    htmlEntities.put("plusmn", new Integer(177));
    htmlEntities.put("sup2", new Integer(178));
    htmlEntities.put("sup3", new Integer(179));
    htmlEntities.put("acute", new Integer(180));
    htmlEntities.put("micro", new Integer(181));
    htmlEntities.put("para", new Integer(182));
    htmlEntities.put("middot", new Integer(183));
    htmlEntities.put("cedil", new Integer(184));
    htmlEntities.put("sup1", new Integer(185));
    htmlEntities.put("ordm", new Integer(186));
    htmlEntities.put("raquo", new Integer(187));
    htmlEntities.put("frac14", new Integer(188));
    htmlEntities.put("frac12", new Integer(189));
    htmlEntities.put("frac34", new Integer(190));
    htmlEntities.put("iquest", new Integer(191));
    htmlEntities.put("Agrave", new Integer(192));
    htmlEntities.put("Aacute", new Integer(193));
    htmlEntities.put("Acirc", new Integer(194));
    htmlEntities.put("Atilde", new Integer(195));
    htmlEntities.put("Auml", new Integer(196));
    htmlEntities.put("Aring", new Integer(197));
    htmlEntities.put("AElig", new Integer(198));
    htmlEntities.put("Ccedil", new Integer(199));
    htmlEntities.put("Egrave", new Integer(200));
    htmlEntities.put("Eacute", new Integer(201));
    htmlEntities.put("Ecirc", new Integer(202));
    htmlEntities.put("Euml", new Integer(203));
    htmlEntities.put("Igrave", new Integer(204));
    htmlEntities.put("Iacute", new Integer(205));
    htmlEntities.put("Icirc", new Integer(206));
    htmlEntities.put("Iuml", new Integer(207));
    htmlEntities.put("ETH", new Integer(208));
    htmlEntities.put("Ntilde", new Integer(209));
    htmlEntities.put("Ograve", new Integer(210));
    htmlEntities.put("Oacute", new Integer(211));
    htmlEntities.put("Ocirc", new Integer(212));
    htmlEntities.put("Otilde", new Integer(213));
    htmlEntities.put("Ouml", new Integer(214));
    htmlEntities.put("times", new Integer(215));
    htmlEntities.put("Oslash", new Integer(216));
    htmlEntities.put("Ugrave", new Integer(217));
    htmlEntities.put("Uacute", new Integer(218));
    htmlEntities.put("Ucirc", new Integer(219));
    htmlEntities.put("Uuml", new Integer(220));
    htmlEntities.put("Yacute", new Integer(221));
    htmlEntities.put("THORN", new Integer(222));
    htmlEntities.put("szlig", new Integer(223));
    htmlEntities.put("agrave", new Integer(224));
    htmlEntities.put("aacute", new Integer(225));
    htmlEntities.put("acirc", new Integer(226));
    htmlEntities.put("atilde", new Integer(227));
    htmlEntities.put("auml", new Integer(228));
    htmlEntities.put("aring", new Integer(229));
    htmlEntities.put("aelig", new Integer(230));
    htmlEntities.put("ccedil", new Integer(231));
    htmlEntities.put("egrave", new Integer(232));
    htmlEntities.put("eacute", new Integer(233));
    htmlEntities.put("ecirc", new Integer(234));
    htmlEntities.put("euml", new Integer(235));
    htmlEntities.put("igrave", new Integer(236));
    htmlEntities.put("iacute", new Integer(237));
    htmlEntities.put("icirc", new Integer(238));
    htmlEntities.put("iuml", new Integer(239));
    htmlEntities.put("eth", new Integer(240));
    htmlEntities.put("ntilde", new Integer(241));
    htmlEntities.put("ograve", new Integer(242));
    htmlEntities.put("oacute", new Integer(243));
    htmlEntities.put("ocirc", new Integer(244));
    htmlEntities.put("otilde", new Integer(245));
    htmlEntities.put("ouml", new Integer(246));
    htmlEntities.put("divide", new Integer(247));
    htmlEntities.put("oslash", new Integer(248));
    htmlEntities.put("ugrave", new Integer(249));
    htmlEntities.put("uacute", new Integer(250));
    htmlEntities.put("ucirc", new Integer(251));
    htmlEntities.put("uuml", new Integer(252));
    htmlEntities.put("yacute", new Integer(253));
    htmlEntities.put("thorn", new Integer(254));
    htmlEntities.put("yuml", new Integer(255));
    htmlEntities.put("fnof", new Integer(402));
    htmlEntities.put("Alpha", new Integer(913));
    htmlEntities.put("Beta", new Integer(914));
    htmlEntities.put("Gamma", new Integer(915));
    htmlEntities.put("Delta", new Integer(916));
    htmlEntities.put("Epsilon", new Integer(917));
    htmlEntities.put("Zeta", new Integer(918));
    htmlEntities.put("Eta", new Integer(919));
    htmlEntities.put("Theta", new Integer(920));
    htmlEntities.put("Iota", new Integer(921));
    htmlEntities.put("Kappa", new Integer(922));
    htmlEntities.put("Lambda", new Integer(923));
    htmlEntities.put("Mu", new Integer(924));
    htmlEntities.put("Nu", new Integer(925));
    htmlEntities.put("Xi", new Integer(926));
    htmlEntities.put("Omicron", new Integer(927));
    htmlEntities.put("Pi", new Integer(928));
    htmlEntities.put("Rho", new Integer(929));
    htmlEntities.put("Sigma", new Integer(931));
    htmlEntities.put("Tau", new Integer(932));
    htmlEntities.put("Upsilon", new Integer(933));
    htmlEntities.put("Phi", new Integer(934));
    htmlEntities.put("Chi", new Integer(935));
    htmlEntities.put("Psi", new Integer(936));
    htmlEntities.put("Omega", new Integer(937));
    htmlEntities.put("alpha", new Integer(945));
    htmlEntities.put("beta", new Integer(946));
    htmlEntities.put("gamma", new Integer(947));
    htmlEntities.put("delta", new Integer(948));
    htmlEntities.put("epsilon", new Integer(949));
    htmlEntities.put("zeta", new Integer(950));
    htmlEntities.put("eta", new Integer(951));
    htmlEntities.put("theta", new Integer(952));
    htmlEntities.put("iota", new Integer(953));
    htmlEntities.put("kappa", new Integer(954));
    htmlEntities.put("lambda", new Integer(955));
    htmlEntities.put("mu", new Integer(956));
    htmlEntities.put("nu", new Integer(957));
    htmlEntities.put("xi", new Integer(958));
    htmlEntities.put("omicron", new Integer(959));
    htmlEntities.put("pi", new Integer(960));
    htmlEntities.put("rho", new Integer(961));
    htmlEntities.put("sigmaf", new Integer(962));
    htmlEntities.put("sigma", new Integer(963));
    htmlEntities.put("tau", new Integer(964));
    htmlEntities.put("upsilon", new Integer(965));
    htmlEntities.put("phi", new Integer(966));
    htmlEntities.put("chi", new Integer(967));
    htmlEntities.put("psi", new Integer(968));
    htmlEntities.put("omega", new Integer(969));
    htmlEntities.put("thetasym", new Integer(977));
    htmlEntities.put("upsih", new Integer(978));
    htmlEntities.put("piv", new Integer(982));
    htmlEntities.put("bull", new Integer(8226));
    htmlEntities.put("hellip", new Integer(8230));
    htmlEntities.put("prime", new Integer(8242));
    htmlEntities.put("Prime", new Integer(8243));
    htmlEntities.put("oline", new Integer(8254));
    htmlEntities.put("frasl", new Integer(8260));
    htmlEntities.put("weierp", new Integer(8472));
    htmlEntities.put("image", new Integer(8465));
    htmlEntities.put("real", new Integer(8476));
    htmlEntities.put("trade", new Integer(8482));
    htmlEntities.put("alefsym", new Integer(8501));
    htmlEntities.put("larr", new Integer(8592));
    htmlEntities.put("uarr", new Integer(8593));
    htmlEntities.put("rarr", new Integer(8594));
    htmlEntities.put("darr", new Integer(8595));
    htmlEntities.put("harr", new Integer(8596));
    htmlEntities.put("crarr", new Integer(8629));
    htmlEntities.put("lArr", new Integer(8656));
    htmlEntities.put("uArr", new Integer(8657));
    htmlEntities.put("rArr", new Integer(8658));
    htmlEntities.put("dArr", new Integer(8659));
    htmlEntities.put("hArr", new Integer(8660));
    htmlEntities.put("forall", new Integer(8704));
    htmlEntities.put("part", new Integer(8706));
    htmlEntities.put("exist", new Integer(8707));
    htmlEntities.put("empty", new Integer(8709));
    htmlEntities.put("nabla", new Integer(8711));
    htmlEntities.put("isin", new Integer(8712));
    htmlEntities.put("notin", new Integer(8713));
    htmlEntities.put("ni", new Integer(8715));
    htmlEntities.put("prod", new Integer(8719));
    htmlEntities.put("sum", new Integer(8721));
    htmlEntities.put("minus", new Integer(8722));
    htmlEntities.put("lowast", new Integer(8727));
    htmlEntities.put("radic", new Integer(8730));
    htmlEntities.put("prop", new Integer(8733));
    htmlEntities.put("infin", new Integer(8734));
    htmlEntities.put("ang", new Integer(8736));
    htmlEntities.put("and", new Integer(8743));
    htmlEntities.put("or", new Integer(8744));
    htmlEntities.put("cap", new Integer(8745));
    htmlEntities.put("cup", new Integer(8746));
    htmlEntities.put("int", new Integer(8747));
    htmlEntities.put("there4", new Integer(8756));
    htmlEntities.put("sim", new Integer(8764));
    htmlEntities.put("cong", new Integer(8773));
    htmlEntities.put("asymp", new Integer(8776));
    htmlEntities.put("ne", new Integer(8800));
    htmlEntities.put("equiv", new Integer(8801));
    htmlEntities.put("le", new Integer(8804));
    htmlEntities.put("ge", new Integer(8805));
    htmlEntities.put("sub", new Integer(8834));
    htmlEntities.put("sup", new Integer(8835));
    htmlEntities.put("nsub", new Integer(8836));
    htmlEntities.put("sube", new Integer(8838));
    htmlEntities.put("supe", new Integer(8839));
    htmlEntities.put("oplus", new Integer(8853));
    htmlEntities.put("otimes", new Integer(8855));
    htmlEntities.put("perp", new Integer(8869));
    htmlEntities.put("sdot", new Integer(8901));
    htmlEntities.put("lceil", new Integer(8968));
    htmlEntities.put("rceil", new Integer(8969));
    htmlEntities.put("lfloor", new Integer(8970));
    htmlEntities.put("rfloor", new Integer(8971));
    htmlEntities.put("lang", new Integer(9001));
    htmlEntities.put("rang", new Integer(9002));
    htmlEntities.put("loz", new Integer(9674));
    htmlEntities.put("spades", new Integer(9824));
    htmlEntities.put("clubs", new Integer(9827));
    htmlEntities.put("hearts", new Integer(9829));
    htmlEntities.put("diams", new Integer(9830));
    htmlEntities.put("quot", new Integer(34));
    htmlEntities.put("amp", new Integer(38));
    htmlEntities.put("lt", new Integer(60));
    htmlEntities.put("gt", new Integer(62));
    htmlEntities.put("OElig", new Integer(338));
    htmlEntities.put("oelig", new Integer(339));
    htmlEntities.put("Scaron", new Integer(352));
    htmlEntities.put("scaron", new Integer(353));
    htmlEntities.put("Yuml", new Integer(376));
    htmlEntities.put("circ", new Integer(710));
    htmlEntities.put("tilde", new Integer(732));
    htmlEntities.put("ensp", new Integer(8194));
    htmlEntities.put("emsp", new Integer(8195));
    htmlEntities.put("thinsp", new Integer(8201));
    htmlEntities.put("zwnj", new Integer(8204));
    htmlEntities.put("zwj", new Integer(8205));
    htmlEntities.put("lrm", new Integer(8206));
    htmlEntities.put("rlm", new Integer(8207));
    htmlEntities.put("ndash", new Integer(8211));
    htmlEntities.put("mdash", new Integer(8212));
    htmlEntities.put("lsquo", new Integer(8216));
    htmlEntities.put("rsquo", new Integer(8217));
    htmlEntities.put("sbquo", new Integer(8218));
    htmlEntities.put("ldquo", new Integer(8220));
    htmlEntities.put("rdquo", new Integer(8221));
    htmlEntities.put("bdquo", new Integer(8222));
    htmlEntities.put("dagger", new Integer(8224));
    htmlEntities.put("Dagger", new Integer(8225));
    htmlEntities.put("permil", new Integer(8240));
    htmlEntities.put("lsaquo", new Integer(8249));
    htmlEntities.put("rsaquo", new Integer(8250));
    htmlEntities.put("euro", new Integer(8364));
  }

  /**
   * Turn any HTML escape entities in the string into
   * characters and return the resulting string.
   *
   * @param s String to be unescaped.
   * @return unescaped String.
   * @throws NullPointerException if s is null.
   *
   * @since ostermillerutils 1.00.00
   */
  public static String unescapeHTML(String s){
    StringBuffer result = new StringBuffer(s.length());
    int ampInd = s.indexOf("&");
    int lastEnd = 0;
    while (ampInd >= 0){
      int nextAmp = s.indexOf("&", ampInd+1);
      int nextSemi = s.indexOf(";", ampInd+1);
      if (nextSemi != -1 && (nextAmp == -1 || nextSemi < nextAmp)){
        int value = -1;
        String escape = s.substring(ampInd+1,nextSemi);
        try {
          if (escape.startsWith("#")){
            value = Integer.parseInt(escape.substring(1), 10);
          } else {
            if (htmlEntities.containsKey(escape)){
              value = ((Integer)(htmlEntities.get(escape))).intValue();
            }
          }
        } catch (NumberFormatException x){
        }
        result.append(s.substring(lastEnd, ampInd));
        lastEnd = nextSemi + 1;
        if (value >= 0 && value <= 0xffff){
          result.append((char)value);
        } else {
          result.append("&").append(escape).append(";");
        }
      }
      ampInd = nextAmp;
    }
    result.append(s.substring(lastEnd));
    return result.toString();
  }
}










6.31.HTML Parser
6.31.1.List Tags
6.31.2.html parser DTD
6.31.3.Use javax.swing.text.html.HTMLEditorKit to parse HTML
6.31.4.extends HTMLEditorKit.ParserCallback
6.31.5.Parse HTML
6.31.6.Convert to HTML string
6.31.7.Escape HTML
6.31.8.Filter message string for characters that are sensitive in HTML
6.31.9.Filter the specified message string for characters that are sensitive in HTML
6.31.10.HTML color names
6.31.11.Text To HTML
6.31.12.Unescape HTML
6.31.13.Utility methods for dealing with HTML
6.31.14.insert HTML block dynamically
6.31.15.A collection of all character entites defined in the HTML4 standard.
6.31.16.Decode an HTML color string like '#F567BA;' into a Color