Java的HTMLDecoder，將HTML特殊字符解碼還原

2019-11-17 04:19:36

字體：大中小

來源：轉載

供稿：網友

package com.laozizhu.search.util;

import java.util.HashMap;

/**
* 替換HTMl里面的字符 e.g.: < > " å И 水
*
* @author 老紫竹(laozizhu.com)
*/
public class HTMLDecoder {

public static final HashMap<String, Character> charTable;

public static String decode(String s) {
    String t;
    Character ch;
    int tmpPos, i;

    int maxPos = s.length();
    StringBuffer sb = new StringBuffer(maxPos);
    int curPos = 0;
    while (curPos < maxPos) {
      char c = s.charAt(curPos++);
      if (c == '&') {
        tmpPos = curPos;
        if (tmpPos < maxPos) {
          char d = s.charAt(tmpPos++);
          if (d == '#') {
            if (tmpPos < maxPos) {
              d = s.charAt(tmpPos++);
              if ((d == 'x') || (d == 'X')) {
                if (tmpPos < maxPos) {
                  d = s.charAt(tmpPos++);
                  if (isHexDigit(d)) {
                    while (tmpPos < maxPos) {
                      d = s.charAt(tmpPos++);
                      if (!isHexDigit(d)) {
                        if (d == ';') {
                          t = s.substring(curPos + 2, tmpPos - 1);
                          try {
                            i = Integer.parseInt(t, 16);
                            if ((i >= 0) && (i < 65536)) {
                              c = (char) i;
                              curPos = tmpPos;
                            }
                          } catch (NumberFormatException e) {
                          }
                        }
                        break;
                      }
                    }
                  }
                }
              } else if (isDigit(d)) {
                while (tmpPos < maxPos) {
                  d = s.charAt(tmpPos++);
                  if (!isDigit(d)) {
                    if (d == ';') {
                      t = s.substring(curPos + 1, tmpPos - 1);
                      try {
                        i = Integer.parseInt(t);
                        if ((i >= 0) && (i < 65536)) {
                          c = (char) i;
                          curPos = tmpPos;
                        }
                      } catch (NumberFormatException e) {
                      }
                    }
                    break;
                  }
                }
              }
            }
          } else if (isLetter(d)) {
            while (tmpPos < maxPos) {
              d = s.charAt(tmpPos++);
              if (!isLetterOrDigit(d)) {
                if (d == ';') {
                  t = s.substring(curPos, tmpPos - 1);
                  ch = (Character) charTable.get(t);
                  if (ch != null) {
                    c = ch.charValue();
                    curPos = tmpPos;
                  }
                }
                break;
              }
            }
          }
        }
      }
      sb.append(c);
    }
    return sb.toString();
}

PRivate static boolean isLetterOrDigit(char c) {
    return isLetter(c) || isDigit(c);
}

private static boolean isHexDigit(char c) {
    return isHexLetter(c) || isDigit(c);
}

private static boolean isLetter(char c) {
    return ((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'));
}

private static boolean isHexLetter(char c) {
    return ((c >= 'a') && (c <= 'f')) || ((c >= 'A') && (c <= 'F'));
}

private static boolean isDigit(char c) {
    return (c >= '0') && (c <= '9');
}

public static String compact(String s) {
    int maxPos = s.length();
    StringBuffer sb = new StringBuffer(maxPos);
    int curPos = 0;
    while (curPos < maxPos) {
      char c = s.charAt(curPos++);
      if (isWhitespace(c)) {
        while ((curPos < maxPos) && isWhitespace(s.charAt(curPos))) {
          curPos++;
        }
        c = '/u0020';
      }
      sb.append(c);
    }
    return sb.toString();
}

// HTML is very particular about what constitutes white space.
public static boolean isWhitespace(char ch) {
    return (ch == '/u0020') || (ch == '/r') || (ch == '/n') || (ch == '/u0009') || (ch == '/u000c') || (ch == '/u200b');
}

static {
    charTable = new HashMap<String, Character>();
    charTable.put("quot", new Character((char) 34));
    charTable.put("amp", new Character((char) 38));
    charTable.put("apos", new Character((char) 39));
    charTable.put("lt", new Character((char) 60));
    charTable.put("gt", new Character((char) 62));
    charTable.put("nbsp", new Character((char) 160));
    charTable.put("iexcl", new Character((char) 161));
    charTable.put("cent", new Character((char) 162));
    charTable.put("pound", new Character((char) 163));
    charTable.put("curren", new Character((char) 164));
    charTable.put("yen", new Character((char) 165));
    charTable.put("brvbar", new Character((char) 166));
    charTable.put("sect", new Character((char) 167));
    charTable.put("uml", new Character((char) 168));
    charTable.put("copy", new Character((char) 169));
    charTable.put("ordf", new Character((char) 170));
    charTable.put("laquo", new Character((char) 171));
    charTable.put("not", new Character((char) 172));
    charTable.put("shy", new Character((char) 173));
    charTable.put("reg", new Character((char) 174));
    charTable.put("macr", new Character((char) 175));
    charTable.put("deg", new Character((char) 176));
    charTable.put("plusmn", new Character((char) 177));
    charTable.put("sup2", new Character((char) 178));
    charTable.put("sup3", new Character((char) 179));
    charTable.put("acute", new Character((char) 180));
    charTable.put("micro", new Character((char) 181));
    charTable.put("para", new Character((char) 182));
    charTable.put("middot", new Character((char) 183));
    charTable.put("cedil", new Character((char) 184));
    charTable.put("sup1", new Character((char) 185));
    charTable.put("ordm", new Character((char) 186));
    charTable.put("raquo", new Character((char) 187));
    charTable.put("frac14", new Character((char) 188));
    charTable.put("frac12", new Character((char) 189));
    charTable.put("frac34", new Character((char) 190));
    charTable.put("iquest", new Character((char) 191));
    charTable.put("Agrave", new Character((char) 192));
    charTable.put("Aacute", new Character((char) 193));
    charTable.put("Acirc", new Character((char) 194));
    charTable.put("Atilde", new Character((char) 195));
    charTable.put("Auml", new Character((char) 196));
    charTable.put("Aring", new Character((char) 197));
    charTable.put("AElig", new Character((char) 198));
    charTable.put("Ccedil", new Character((char) 199));
    charTable.put("Egrave", new Character((char) 200));
    charTable.put("Eacute", new Character((char) 201));
    charTable.put("Ecirc", new Character((char) 202));
    charTable.put("Euml", new Character((char) 203));
    charTable.put("Igrave", new Character((char) 204));
    charTable.put("Iacute", new Character((char) 205));
    charTable.put("Icirc", new Character((char) 206));
    charTable.put("Iuml", new Character((char) 207));
    charTable.put("ETH", new Character((char) 208));
    charTable.put("Ntilde", new Character((char) 209));
    charTable.put("Ograve", new Character((char) 210));
    charTable.put("Oacute", new Character((char) 211));
    charTable.put("Ocirc", new Character((char) 212));
    charTable.put("Otilde", new Character((char) 213));
    charTable.put("Ouml", new Character((char) 214));
    charTable.put("times", new Character((char) 215));
    charTable.put("Oslash", new Character((char) 216));
    charTable.put("Ugrave", new Character((char) 217));
    charTable.put("Uacute", new Character((char) 218));
    charTable.put("Ucirc", new Character((char) 219));
    charTable.put("Uuml", new Character((char) 220));
    charTable.put("Yacute", new Character((char) 221));
    charTable.put("THORN", new Character((char) 222));
    charTable.put("szlig", new Character((char) 223));
    charTable.put("agrave", new Character((char) 224));
    charTable.put("aacute", new Character((char) 225));
    charTable.put("acirc", new Character((char) 226));
    charTable.put("atilde", new Character((char) 227));
    charTable.put("auml", new Character((char) 228));
    charTable.put("aring", new Character((char) 229));
    charTable.put("aelig", new Character((char) 230));
    charTable.put("ccedil", new Character((char) 231));
    charTable.put("egrave", new Character((char) 232));
    charTable.put("eacute", new Character((char) 233));
    charTable.put("ecirc", new Character((char) 234));
    charTable.put("euml", new Character((char) 235));
    charTable.put("igrave", new Character((char) 236));
    charTable.put("iacute", new Character((char) 237));
    charTable.put("icirc", new Character((char) 238));
    charTable.put("iuml", new Character((char) 239));
    charTable.put("eth", new Character((char) 240));
    charTable.put("ntilde", new Character((char) 241));
    charTable.put("ograve", new Character((char) 242));
    charTable.put("oacute", new Character((char) 243));
    charTable.put("ocirc", new Character((char) 244));
    charTable.put("otilde", new Character((char) 245));
    charTable.put("ouml", new Character((char) 246));
    charTable.put("divide", new Character((char) 247));
    charTable.put("oslash", new Character((char) 248));
    charTable.put("ugrave", new Character((char) 249));
    charTable.put("uacute", new Character((char) 250));
    charTable.put("ucirc", new Character((char) 251));
    charTable.put("uuml", new Character((char) 252));
    charTable.put("yacute", new Character((char) 253));
    charTable.put("thorn", new Character((char) 254));
    charTable.put("yuml", new Character((char) 255));
    charTable.put("OElig", new Character((char) 338));
    charTable.put("oelig", new Character((char) 339));
    charTable.put("Scaron", new Character((char) 352));
    charTable.put("scaron", new Character((char) 353));
    charTable.put("fnof", new Character((char) 402));
    charTable.put("circ", new Character((char) 710));
    charTable.put("tilde", new Character((char) 732));
    charTable.put("Alpha", new Character((char) 913));
    charTable.put("Beta", new Character((char) 914));
    charTable.put("Gamma", new Character((char) 915));
    charTable.put("Delta", new Character((char) 916));
    charTable.put("Epsilon", new Character((char) 917));
    charTable.put("Zeta", new Character((char) 918));
    charTable.put("Eta", new Character((char) 919));
    charTable.put("Theta", new Character((char) 920));
    charTable.put("Iota", new Character((char) 921));
    charTable.put("Kappa", new Character((char) 922));
    charTable.put("Lambda", new Character((char) 923));
    charTable.put("Mu", new Character((char) 924));
    charTable.put("Nu", new Character((char) 925));
    charTable.put("Xi", new Character((char) 926));
    charTable.put("Omicron", new Character((char) 927));
    charTable.put("Pi", new Character((char) 928));
    charTable.put("Rho", new Character((char) 929));
    charTable.put("Sigma", new Character((char) 931));
    charTable.put("Tau", new Character((char) 932));
    charTable.put("Upsilon", new Character((char) 933));
    charTable.put("Phi", new Character((char) 934));
    charTable.put("Chi", new Character((char) 935));
    charTable.put("Psi", new Character((char) 936));
    charTable.put("Omega", new Character((char) 937));
    charTable.put("alpha", new Character((char) 945));
    charTable.put("beta", new Character((char) 946));
    charTable.put("gamma", new Character((char) 947));
    charTable.put("delta", new Character((char) 948));
    charTable.put("epsilon", new Character((char) 949));
    charTable.put("zeta", new Character((char) 950));
    charTable.put("eta", new Character((char) 951));
    charTable.put("theta", new Character((char) 952));
    charTable.put("iota", new Character((char) 953));
    charTable.put("kappa", new Character((char) 954));
    charTable.put("lambda", new Character((char) 955));
    charTable.put("mu", new Character((char) 956));
    charTable.put("nu", new Character((char) 957));
    charTable.put("xi", new Character((char) 958));
    charTable.put("omicron", new Character((char) 959));
    charTable.put("pi", new Character((char) 960));
    charTable.put("rho", new Character((char) 961));
    charTable.put("sigmaf", new Character((char) 962));
    charTable.put("sigma", new Character((char) 963));
    charTable.put("tau", new Character((char) 964));
    charTable.put("upsilon", new Character((char) 965));
    charTable.put("phi", new Character((char) 966));
    charTable.put("chi", new Character((char) 967));
    charTable.put("psi", new Character((char) 968));
    charTable.put("omega", new Character((char) 969));
    charTable.put("thetasym", new Character((char) 977));
    charTable.put("upsih", new Character((char) 978));
    charTable.put("piv", new Character((char) 982));
    charTable.put("ensp", new Character((char) 8194));
    charTable.put("emsp", new Character((char) 8195));
    charTable.put("thinsp", new Character((char) 8201));
    charTable.put("zwnj", new Character((char) 8204));
    charTable.put("zwj", new Character((char) 8205));
    charTable.put("lrm", new Character((char) 8206));
    charTable.put("rlm", new Character((char) 8207));
    charTable.put("ndash", new Character((char) 8211));
    charTable.put("mdash", new Character((char) 8212));
    charTable.put("lsquo", new Character((char) 8216));
    charTable.put("rsquo", new Character((char) 8217));
    charTable.put("sbquo", new Character((char) 8218));
    charTable.put("ldquo", new Character((char) 8220));
    charTable.put("rdquo", new Character((char) 8221));
    charTable.put("bdquo", new Character((char) 8222));
    charTable.put("dagger", new Character((char) 8224));
    charTable.put("Dagger", new Character((char) 8225));
    charTable.put("bull", new Character((char) 8226));
    charTable.put("hell    charTable.put("permil", new Character((char) 8240));
    charTable.put("prime", new Character((char) 8242));
    charTable.put("Prime", new Character((char) 8243));
    charTable.put("lsaquo", new Character((char) 8249));
    charTable.put("rsaquo", new Character((char) 8250));
    charTable.put("oline", new Character((char) 8254));
    charTable.put("frasl", new Character((char) 8260));
    charTable.put("euro", new Character((char) 8364));
    charTable.put("image", new Character((char) 8465));
    charTable.put("weierp", new Character((char) 8472));
    charTable.put("real", new Character((char) 8476));
    charTable.put("trade", new Character((char) 8482));
    charTable.put("alefsym", new Character((char) 8501));
    charTable.put("larr", new Character((char) 8592));
    charTable.put("uarr", new Character((char) 8593));
    charTable.put("rarr", new Character((char) 8594));
    charTable.put("darr", new Character((char) 8595));
    charTable.put("harr", new Character((char) 8596));
    charTable.put("crarr", new Character((char) 8629));
    charTable.put("lArr", new Character((char) 8656));
    charTable.put("uArr", new Character((char) 8657));
    charTable.put("rArr", new Character((char) 8658));
    charTable.put("dArr", new Character((char) 8659));
    charTable.put("hArr", new Character((char) 8660));
    charTable.put("forall", new Character((char) 8704));
    charTable.put("part", new Character((char) 8706));
    charTable.put("exist", new Character((char) 8707));
    charTable.put("empty", new Character((char) 8709));
    charTable.put("nabla", new Character((char) 8711));
    charTable.put("isin", new Character((char) 8712));
    charTable.put("notin", new Character((char) 8713));
    charTable.put("ni", new Character((char) 8715));
    charTable.put("prod", new Character((char) 8719));
    charTable.put("sum", new Character((char) 8721));
    charTable.put("minus", new Character((char) 8722));
    charTable.put("lowast", new Character((char) 8727));
    charTable.put("radic", new Character((char) 8730));
    charTable.put("prop", new Character((char) 8733));
    charTable.put("infin", new Character((char) 8734));
    charTable.put("ang", new Character((char) 8736));
    charTable.put("and", new Character((char) 8743));
    charTable.put("or", new Character((char) 8744));
    charTable.put("cap", new Character((char) 8745));
    charTable.put("cup", new Character((char) 8746));
    charTable.put("int", new Character((char) 8747));
    charTable.put("there4", new Character((char) 8756));
    charTable.put("sim", new Character((char) 8764));
    charTable.put("cong", new Character((char) 8773));
    charTable.put("asymp", new Character((char) 8776));
    charTable.put("ne", new Character((char) 8800));
    charTable.put("equiv", new Character((char) 8801));
    charTable.put("le", new Character((char) 8804));
    charTable.put("ge", new Character((char) 8805));
    charTable.put("sub", new Character((char) 8834));
    charTable.put("sup", new Character((char) 8835));
    charTable.put("nsub", new Character((char) 8836));
    charTable.put("sube", new Character((char) 8838));
    charTable.put("supe", new Character((char) 8839));
    charTable.put("oplus", new Character((char) 8853));
    charTable.put("otimes", new Character((char) 8855));
    charTable.put("perp", new Character((char) 8869));
    charTable.put("sdot", new Character((char) 8901));
    charTable.put("lceil", new Character((char) 8968));
    charTable.put("rceil", new Character((char) 8969));
    charTable.put("lfloor", new Character((char) 8970));
    charTable.put("rfloor", new Character((char) 8971));
    charTable.put("lang", new Character((char) 9001));
    charTable.put("rang", new Character((char) 9002));
    charTable.put("loz", new Character((char) 9674));
    charTable.put("spades", new Character((char) 9824));
    charTable.put("clubs", new Character((char) 9827));
    charTable.put("hearts", new Character((char) 9829));
    charTable.put("diams", new Character((char) 9830));
}
}
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