1. /*

  2.  * @(#)HTML.java	1.41 03/12/19

  3.  *

  4.  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.

  5.  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

  6.  */

  7. package javax.swing.text.html;

  8. 

  9. import java.io.*;

  10. import java.util.Hashtable;

  11. import javax.swing.text.AttributeSet;

  12. import javax.swing.text.StyleConstants;

  13. import javax.swing.text.StyleContext;

  14. 

  15. /**

  16.  * Constants used in the <code>HTMLDocument</code>.  These

  17.  * are basically tag and attribute definitions.

  18.  *

  19.  * @author  Timothy Prinzing

  20.  * @author  Sunita Mani

  21.  *

  22.  * @version 1.41 12/19/03

  23.  */

  24. public class HTML {

  25. 

  26.     /**

  27.      * Typesafe enumeration for an HTML tag.  Although the

  28.      * set of HTML tags is a closed set, we have left the

  29.      * set open so that people can add their own tag types

  30.      * to their custom parser and still communicate to the

  31.      * reader.

  32.      */

  33.     public static class Tag {

  34. 

  35. 	/** @since 1.3 */

  36. 	public Tag() {}

  37. 

  38.         /**

  39.          * Creates a new <code>Tag</code> with the specified <code>id</code>,

  40.          * and with <code>causesBreak</code> and <code>isBlock</code>

  41.          * set to <code>false</code>.

  42.          *

  43.          * @param id  the id of the new tag

  44.          */

  45.         protected Tag(String id) {

  46. 	    this(id, false, false);

  47. 	}

  48. 

  49.         /**

  50.          * Creates a new <code>Tag</code> with the specified <code>id</code>

  51.          * <code>causesBreak</code> and <code>isBlock</code> are defined

  52.          * by the user.

  53.          *

  54.          * @param id the id of the new tag

  55.          * @param causesBreak  <code>true</code> if this tag

  56.          *    causes a break to the flow of data

  57.          * @param isBlock <code>true</code> if the tag is used

  58.          *    to add structure to a document

  59.          */

  60. 	protected Tag(String id, boolean causesBreak, boolean isBlock) {

  61. 	    name = id;

  62. 	    this.breakTag = causesBreak;

  63. 	    this.blockTag = isBlock;

  64. 	}

  65. 

  66. 	/**

  67.          * Returns <code>true</code> if this tag is a block

  68.          * tag, which is a tag used to add structure to a

  69.          * document.

  70. 	 * 

  71.          * @return <code>true</code> if this tag is a block

  72.          *   tag, otherwise returns <code>false</code>

  73. 	 */

  74. 	public boolean isBlock() {

  75. 	    return blockTag;

  76. 	}

  77. 

  78. 	/**

  79.          * Returns <code>true</code> if this tag causes a

  80.          * line break to the flow of data, otherwise returns

  81.          * <code>false</code>.

  82. 	 * 

  83. 	 * @return <code>true</code> if this tag causes a

  84.          *   line break to the flow of data, otherwise returns

  85.          *   <code>false</code>

  86. 	 */

  87. 	public boolean breaksFlow() {

  88. 	    return breakTag;

  89. 	}

  90. 

  91. 	/**

  92. 	 * Returns <code>true</code> if this tag is pre-formatted,

  93.          * which is true if the tag is either <code>PRE</code> or

  94.          * <code>TEXTAREA</code>.

  95.          *

  96.          * @return <code>true</code> if this tag is pre-formatted,

  97.          *   otherwise returns <code>false</code>

  98. 	 */

  99. 	public boolean isPreformatted() {

  100. 	    return (this == PRE || this == TEXTAREA);

  101. 	}

  102. 

  103. 	/**

  104. 	 * Returns the string representation of the

  105. 	 * tag.

  106.          *

  107.          * @return the <code>String</code> representation of the tag

  108. 	 */

  109.         public String toString() {

  110. 	    return name;

  111. 	}

  112. 

  113. 	boolean blockTag;

  114. 	boolean breakTag;

  115. 	String name;

  116. 	boolean unknown;

  117. 

  118.     	// --- Tag Names -----------------------------------

  119. 

  120.     	public static final Tag A = new Tag("a");

  121.     	public static final Tag ADDRESS = new Tag("address");

  122.     	public static final Tag APPLET = new Tag("applet");

  123.     	public static final Tag AREA = new Tag("area");

  124.     	public static final Tag B = new Tag("b");

  125.     	public static final Tag BASE = new Tag("base");

  126.     	public static final Tag BASEFONT = new Tag("basefont");

  127.     	public static final Tag BIG = new Tag("big");

  128.     	public static final Tag BLOCKQUOTE = new Tag("blockquote", true, true);

  129.     	public static final Tag BODY = new Tag("body", true, true);

  130.     	public static final Tag BR = new Tag("br", true, false);

  131.     	public static final Tag CAPTION = new Tag("caption");

  132.     	public static final Tag CENTER = new Tag("center", true, false);

  133.     	public static final Tag CITE = new Tag("cite");

  134.     	public static final Tag CODE = new Tag("code");

  135.     	public static final Tag DD = new Tag("dd", true, true);

  136.     	public static final Tag DFN = new Tag("dfn");

  137.     	public static final Tag DIR = new Tag("dir", true, true);

  138.     	public static final Tag DIV = new Tag("div", true, true);

  139.     	public static final Tag DL = new Tag("dl", true, true);

  140.     	public static final Tag DT = new Tag("dt", true, true);

  141.     	public static final Tag EM = new Tag("em");

  142.     	public static final Tag FONT = new Tag("font");

  143.     	public static final Tag FORM = new Tag("form", true, false);

  144. 	public static final Tag FRAME = new Tag("frame");

  145. 	public static final Tag FRAMESET = new Tag("frameset");

  146.     	public static final Tag H1 = new Tag("h1", true, true);

  147.     	public static final Tag H2 = new Tag("h2", true, true);

  148.     	public static final Tag H3 = new Tag("h3", true, true);

  149.     	public static final Tag H4 = new Tag("h4", true, true);

  150.     	public static final Tag H5 = new Tag("h5", true, true);

  151.     	public static final Tag H6 = new Tag("h6", true, true);

  152.     	public static final Tag HEAD = new Tag("head", true, true);

  153.     	public static final Tag HR = new Tag("hr", true, false);

  154.     	public static final Tag HTML = new Tag("html", true, false);

  155.     	public static final Tag I = new Tag("i");

  156.     	public static final Tag IMG = new Tag("img");

  157.     	public static final Tag INPUT = new Tag("input");

  158.     	public static final Tag ISINDEX = new Tag("isindex", true, false);

  159.     	public static final Tag KBD = new Tag("kbd");

  160.     	public static final Tag LI = new Tag("li", true, true);

  161.     	public static final Tag LINK = new Tag("link");

  162.     	public static final Tag MAP = new Tag("map");

  163.     	public static final Tag MENU = new Tag("menu", true, true);

  164.     	public static final Tag META = new Tag("meta");

  165. 	/*public*/ static final Tag NOBR = new Tag("nobr");

  166. 	public static final Tag NOFRAMES = new Tag("noframes", true, true);

  167.     	public static final Tag OBJECT = new Tag("object");

  168.     	public static final Tag OL = new Tag("ol", true, true);

  169.     	public static final Tag OPTION = new Tag("option");

  170.     	public static final Tag P = new Tag("p", true, true);

  171.     	public static final Tag PARAM = new Tag("param");

  172.     	public static final Tag PRE = new Tag("pre", true, true);

  173.     	public static final Tag SAMP = new Tag("samp");

  174.     	public static final Tag SCRIPT = new Tag("script");

  175.     	public static final Tag SELECT = new Tag("select");

  176.     	public static final Tag SMALL = new Tag("small");

  177.     	public static final Tag SPAN = new Tag("span");

  178.     	public static final Tag STRIKE = new Tag("strike");

  179.     	public static final Tag S = new Tag("s");

  180.     	public static final Tag STRONG = new Tag("strong");

  181.     	public static final Tag STYLE = new Tag("style");

  182.     	public static final Tag SUB = new Tag("sub");

  183.     	public static final Tag SUP = new Tag("sup");

  184.     	public static final Tag TABLE = new Tag("table", false, true);

  185.     	public static final Tag TD = new Tag("td", true, true);

  186.     	public static final Tag TEXTAREA = new Tag("textarea");

  187.     	public static final Tag TH = new Tag("th", true, true);

  188.     	public static final Tag TITLE = new Tag("title", true, true);

  189.     	public static final Tag TR = new Tag("tr", false, true);

  190.     	public static final Tag TT = new Tag("tt");

  191.     	public static final Tag U = new Tag("u");

  192.     	public static final Tag UL = new Tag("ul", true, true);

  193.     	public static final Tag VAR = new Tag("var");

  194. 

  195. 	/**

  196. 	 * All text content must be in a paragraph element.

  197. 	 * If a paragraph didn't exist when content was

  198. 	 * encountered, a paragraph is manufactured.

  199. 	 * <p>

  200. 	 * This is a tag synthesized by the HTML reader.

  201. 	 * Since elements are identified by their tag type,

  202. 	 * we create a some fake tag types to mark the elements

  203. 	 * that were manufactured.

  204. 	 */

  205. 	public static final Tag IMPLIED = new Tag("p-implied");

  206. 

  207. 	/**

  208. 	 * All text content is labeled with this tag.

  209. 	 * <p>

  210. 	 * This is a tag synthesized by the HTML reader.

  211. 	 * Since elements are identified by their tag type,

  212. 	 * we create a some fake tag types to mark the elements

  213. 	 * that were manufactured.

  214. 	 */

  215. 	public static final Tag CONTENT = new Tag("content");

  216. 

  217. 	/**

  218. 	 * All comments are labeled with this tag.

  219. 	 * <p>

  220. 	 * This is a tag synthesized by the HTML reader.

  221. 	 * Since elements are identified by their tag type,

  222. 	 * we create a some fake tag types to mark the elements

  223. 	 * that were manufactured.

  224. 	 */

  225. 	public static final Tag COMMENT = new Tag("comment");

  226. 

  227. 	static final Tag allTags[]  = {

  228. 	    A, ADDRESS, APPLET, AREA, B, BASE, BASEFONT, BIG,

  229. 	    BLOCKQUOTE, BODY, BR, CAPTION, CENTER, CITE, CODE,

  230. 	    DD, DFN, DIR, DIV, DL, DT, EM, FONT, FORM, FRAME,

  231. 	    FRAMESET, H1, H2, H3, H4, H5, H6, HEAD, HR, HTML,

  232. 	    I, IMG, INPUT, ISINDEX, KBD, LI, LINK, MAP, MENU,

  233. 	    META, NOBR, NOFRAMES, OBJECT, OL, OPTION, P, PARAM,

  234. 	    PRE, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, S,

  235. 	    STRONG, STYLE, SUB, SUP, TABLE, TD, TEXTAREA,

  236. 	    TH, TITLE, TR, TT, U, UL, VAR	

  237. 	};

  238. 

  239. 	static {

  240. 	    // Force HTMLs static initialize to be loaded.

  241. 	    getTag("html");

  242. 	}

  243.     }

  244. 

  245.     // There is no unique instance of UnknownTag, so we allow it to be

  246.     // Serializable.

  247.     public static class UnknownTag extends Tag implements Serializable {

  248. 	

  249.         /**

  250.          * Creates a new <code>UnknownTag</code> with the specified

  251.          * <code>id</code>.

  252.          * @param id the id of the new tag

  253.          */

  254. 	public UnknownTag(String id) {

  255. 	    super(id);

  256. 	}

  257. 

  258.         /**

  259.          * Returns the hash code which corresponds to the string

  260.          * for this tag.

  261.          */

  262. 	public int hashCode() {

  263. 	    return toString().hashCode();

  264. 	}

  265. 

  266. 	/**

  267. 	 * Compares this object to the specifed object.

  268. 	 * The result is <code>true</code> if and only if the argument is not

  269. 	 * <code>null</code> and is an <code>UnknownTag</code> object

  270.          * with the same name.

  271.          *

  272. 	 * @param     obj   the object to compare this tag with

  273. 	 * @return    <code>true</code> if the objects are equal;

  274. 	 *            <code>false</code> otherwise

  275. 	 */

  276.         public boolean equals(Object obj) {

  277. 	    if (obj instanceof UnknownTag) {

  278. 		return toString().equals(obj.toString());

  279. 	    }

  280. 	    return false;

  281. 	}

  282. 

  283. 	private void writeObject(java.io.ObjectOutputStream s)

  284. 	             throws IOException {

  285. 	    s.defaultWriteObject();

  286. 	    s.writeBoolean(blockTag);

  287. 	    s.writeBoolean(breakTag);

  288. 	    s.writeBoolean(unknown);

  289. 	    s.writeObject(name);

  290. 	}

  291. 

  292. 	private void readObject(ObjectInputStream s)

  293. 	    throws ClassNotFoundException, IOException {

  294. 	    s.defaultReadObject();

  295. 	    blockTag = s.readBoolean();

  296. 	    breakTag = s.readBoolean();

  297. 	    unknown = s.readBoolean();

  298. 	    name = (String)s.readObject();

  299. 	}

  300.     }

  301. 

  302.     /**

  303.      * Typesafe enumeration representing an HTML

  304.      * attribute.

  305.      */

  306.     public static final class Attribute {

  307. 

  308.         /**

  309.          * Creates a new <code>Attribute</code> with the specified

  310.          * <code>id</code>.

  311.          *

  312.          * @param id the id of the new <code>Attribute</code>

  313.          */

  314. 	Attribute(String id) {

  315. 	    name = id;

  316. 	}

  317. 

  318.         /**

  319.          * Returns the string representation of this attribute.

  320.          * @return the string representation of this attribute

  321.          */

  322. 	public String toString() {

  323. 	    return name;

  324. 	}

  325. 

  326. 	private String name;

  327. 

  328. 	public static final Attribute SIZE = new Attribute("size");

  329. 	public static final Attribute COLOR = new Attribute("color");

  330. 	public static final Attribute CLEAR = new Attribute("clear");

  331. 	public static final Attribute BACKGROUND = new Attribute("background");

  332. 	public static final Attribute BGCOLOR = new Attribute("bgcolor");

  333. 	public static final Attribute TEXT = new Attribute("text");

  334. 	public static final Attribute LINK = new Attribute("link");

  335. 	public static final Attribute VLINK = new Attribute("vlink");

  336. 	public static final Attribute ALINK = new Attribute("alink");

  337. 	public static final Attribute WIDTH = new Attribute("width");

  338. 	public static final Attribute HEIGHT = new Attribute("height");

  339. 	public static final Attribute ALIGN = new Attribute("align");

  340. 	public static final Attribute NAME = new Attribute("name");

  341. 	public static final Attribute HREF = new Attribute("href");

  342. 	public static final Attribute REL = new Attribute("rel");

  343. 	public static final Attribute REV = new Attribute("rev");

  344. 	public static final Attribute TITLE = new Attribute("title");

  345. 	public static final Attribute TARGET = new Attribute("target");

  346. 	public static final Attribute SHAPE = new Attribute("shape");

  347. 	public static final Attribute COORDS = new Attribute("coords");

  348. 	public static final Attribute ISMAP = new Attribute("ismap");

  349. 	public static final Attribute NOHREF = new Attribute("nohref");

  350. 	public static final Attribute ALT = new Attribute("alt");

  351. 	public static final Attribute ID = new Attribute("id");

  352. 	public static final Attribute SRC = new Attribute("src");

  353. 	public static final Attribute HSPACE = new Attribute("hspace");

  354. 	public static final Attribute VSPACE = new Attribute("vspace");

  355. 	public static final Attribute USEMAP = new Attribute("usemap");

  356. 	public static final Attribute LOWSRC = new Attribute("lowsrc");

  357. 	public static final Attribute CODEBASE = new Attribute("codebase");

  358. 	public static final Attribute CODE = new Attribute("code");

  359. 	public static final Attribute ARCHIVE = new Attribute("archive");

  360. 	public static final Attribute VALUE = new Attribute("value");

  361. 	public static final Attribute VALUETYPE = new Attribute("valuetype");

  362. 	public static final Attribute TYPE = new Attribute("type");

  363. 	public static final Attribute CLASS = new Attribute("class");

  364. 	public static final Attribute STYLE = new Attribute("style");

  365. 	public static final Attribute LANG = new Attribute("lang");

  366. 	public static final Attribute FACE = new Attribute("face");

  367. 	public static final Attribute DIR = new Attribute("dir");

  368. 	public static final Attribute DECLARE = new Attribute("declare");

  369. 	public static final Attribute CLASSID = new Attribute("classid");

  370. 	public static final Attribute DATA = new Attribute("data");

  371. 	public static final Attribute CODETYPE = new Attribute("codetype");

  372. 	public static final Attribute STANDBY = new Attribute("standby");

  373. 	public static final Attribute BORDER = new Attribute("border");

  374. 	public static final Attribute SHAPES = new Attribute("shapes");

  375. 	public static final Attribute NOSHADE = new Attribute("noshade");

  376. 	public static final Attribute COMPACT = new Attribute("compact");

  377. 	public static final Attribute START = new Attribute("start");

  378. 	public static final Attribute ACTION = new Attribute("action");

  379. 	public static final Attribute METHOD = new Attribute("method");

  380. 	public static final Attribute ENCTYPE = new Attribute("enctype");

  381. 	public static final Attribute CHECKED = new Attribute("checked");

  382. 	public static final Attribute MAXLENGTH = new Attribute("maxlength");

  383. 	public static final Attribute MULTIPLE = new Attribute("multiple");

  384. 	public static final Attribute SELECTED = new Attribute("selected");

  385. 	public static final Attribute ROWS = new Attribute("rows");

  386. 	public static final Attribute COLS = new Attribute("cols");

  387. 	public static final Attribute DUMMY = new Attribute("dummy");

  388. 	public static final Attribute CELLSPACING = new Attribute("cellspacing");

  389. 	public static final Attribute CELLPADDING = new Attribute("cellpadding");

  390. 	public static final Attribute VALIGN = new Attribute("valign");

  391. 	public static final Attribute HALIGN = new Attribute("halign");

  392. 	public static final Attribute NOWRAP = new Attribute("nowrap");

  393. 	public static final Attribute ROWSPAN = new Attribute("rowspan");

  394. 	public static final Attribute COLSPAN = new Attribute("colspan");

  395. 	public static final Attribute PROMPT = new Attribute("prompt");

  396. 	public static final Attribute HTTPEQUIV = new Attribute("http-equiv");

  397. 	public static final Attribute CONTENT = new Attribute("content");

  398. 	public static final Attribute LANGUAGE = new Attribute("language");

  399. 	public static final Attribute VERSION = new Attribute("version");

  400. 	public static final Attribute N = new Attribute("n");

  401. 	public static final Attribute FRAMEBORDER = new Attribute("frameborder");

  402. 	public static final Attribute MARGINWIDTH = new Attribute("marginwidth");

  403. 	public static final Attribute MARGINHEIGHT = new Attribute("marginheight");

  404. 	public static final Attribute SCROLLING = new Attribute("scrolling");

  405. 	public static final Attribute NORESIZE = new Attribute("noresize");

  406. 	public static final Attribute ENDTAG = new Attribute("endtag");

  407. 	public static final Attribute COMMENT = new Attribute("comment");

  408. 	static final Attribute MEDIA = new Attribute("media");

  409. 

  410. 	static final Attribute allAttributes[] = {

  411. 	    FACE,

  412. 	    COMMENT,

  413. 	    SIZE,

  414. 	    COLOR,

  415. 	    CLEAR,

  416. 	    BACKGROUND,

  417. 	    BGCOLOR,

  418. 	    TEXT,

  419. 	    LINK,

  420. 	    VLINK,

  421. 	    ALINK,

  422. 	    WIDTH,

  423. 	    HEIGHT,

  424. 	    ALIGN,

  425. 	    NAME,

  426. 	    HREF,

  427.             REL,

  428.             REV,

  429.             TITLE,

  430.             TARGET,

  431.             SHAPE,

  432.             COORDS,

  433.             ISMAP,

  434.             NOHREF,

  435.             ALT,

  436.             ID,

  437.             SRC,

  438.             HSPACE,

  439.             VSPACE,

  440.             USEMAP,

  441.             LOWSRC,

  442.             CODEBASE,

  443.             CODE,

  444.             ARCHIVE,

  445.             VALUE,

  446.             VALUETYPE,

  447.             TYPE,

  448.             CLASS,

  449.             STYLE,

  450.             LANG,

  451.             DIR,

  452.             DECLARE,

  453.             CLASSID,

  454.             DATA,

  455.             CODETYPE,

  456.             STANDBY,

  457.             BORDER,

  458.             SHAPES,

  459.             NOSHADE,

  460.             COMPACT,

  461.             START,

  462.             ACTION,

  463.             METHOD,

  464.             ENCTYPE,

  465.             CHECKED,

  466.             MAXLENGTH,

  467.             MULTIPLE,

  468.             SELECTED,

  469.             ROWS,

  470.             COLS,

  471.             DUMMY,

  472.             CELLSPACING,

  473.             CELLPADDING,

  474.             VALIGN,

  475.             HALIGN,

  476.             NOWRAP,

  477.             ROWSPAN,

  478.             COLSPAN,

  479.             PROMPT,

  480.             HTTPEQUIV,

  481.             CONTENT,

  482.             LANGUAGE,

  483.             VERSION,

  484.             N,

  485.             FRAMEBORDER,

  486.             MARGINWIDTH,

  487.             MARGINHEIGHT,

  488.             SCROLLING,

  489.             NORESIZE,

  490.             MEDIA,

  491. 	    ENDTAG

  492. 	};

  493.     }

  494. 

  495.     // The secret to 73, is that, given that the Hashtable contents

  496.     // never change once the static initialization happens, the initial size 

  497.     // that the hashtable grew to was determined, and then that very size

  498.     // is used.

  499.     //

  500.     private static final Hashtable tagHashtable = new Hashtable(73);

  501. 

  502.     /** Maps from StyleConstant key to HTML.Tag. */

  503.     private static final Hashtable scMapping = new Hashtable(8);

  504. 

  505.     static {

  506. 

  507. 	for (int i = 0; i < Tag.allTags.length; i++ ) {

  508. 	    tagHashtable.put(Tag.allTags[i].toString(), Tag.allTags[i]);

  509. 	    StyleContext.registerStaticAttributeKey(Tag.allTags[i]);

  510. 	}

  511. 	StyleContext.registerStaticAttributeKey(Tag.IMPLIED);

  512. 	StyleContext.registerStaticAttributeKey(Tag.CONTENT);

  513. 	StyleContext.registerStaticAttributeKey(Tag.COMMENT);

  514. 	for (int i = 0; i < Attribute.allAttributes.length; i++) {

  515. 	    StyleContext.registerStaticAttributeKey(Attribute.

  516. 						    allAttributes[i]);

  517. 	}

  518. 	StyleContext.registerStaticAttributeKey(HTML.NULL_ATTRIBUTE_VALUE);

  519.         scMapping.put(StyleConstants.Bold, Tag.B);

  520.         scMapping.put(StyleConstants.Italic, Tag.I);

  521.         scMapping.put(StyleConstants.Underline, Tag.U);

  522.         scMapping.put(StyleConstants.StrikeThrough, Tag.STRIKE);

  523.         scMapping.put(StyleConstants.Superscript, Tag.SUP);

  524.         scMapping.put(StyleConstants.Subscript, Tag.SUB);

  525.         scMapping.put(StyleConstants.FontFamily, Tag.FONT);

  526.         scMapping.put(StyleConstants.FontSize, Tag.FONT);

  527.     }

  528. 

  529.     /**

  530.      * Returns the set of actual HTML tags that

  531.      * are recognized by the default HTML reader.

  532.      * This set does not include tags that are

  533.      * manufactured by the reader.

  534.      */

  535.     public static Tag[] getAllTags() {

  536. 	Tag[] tags = new Tag[Tag.allTags.length];

  537. 	System.arraycopy(Tag.allTags, 0, tags, 0, Tag.allTags.length);

  538. 	return tags;

  539.     }

  540. 

  541.     /**

  542.      * Fetches a tag constant for a well-known tag name (i.e. one of

  543.      * the tags in the set {A, ADDRESS, APPLET, AREA, B,

  544.      * BASE, BASEFONT, BIG,

  545.      * BLOCKQUOTE, BODY, BR, CAPTION, CENTER, CITE, CODE,

  546.      * DD, DFN, DIR, DIV, DL, DT, EM, FONT, FORM, FRAME,

  547.      * FRAMESET, H1, H2, H3, H4, H5, H6, HEAD, HR, HTML,

  548.      * I, IMG, INPUT, ISINDEX, KBD, LI, LINK, MAP, MENU,

  549.      * META, NOBR, NOFRAMES, OBJECT, OL, OPTION, P, PARAM,

  550.      * PRE, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, S,

  551.      * STRONG, STYLE, SUB, SUP, TABLE, TD, TEXTAREA,

  552.      * TH, TITLE, TR, TT, U, UL, VAR}.  If the given

  553.      * name does not represent one of the well-known tags, then

  554.      * <code>null</code> will be returned.

  555.      *

  556.      * @param tagName the <code>String</code> name requested

  557.      * @return a tag constant corresponding to the <code>tagName</code>,

  558.      *    or <code>null</code> if not found

  559.      */

  560.     public static Tag getTag(String tagName) {

  561. 

  562. 	Object t =  tagHashtable.get(tagName);

  563. 	return (t == null ? null : (Tag)t);

  564.     }

  565. 

  566.     /**

  567.      * Returns the HTML <code>Tag</code> associated with the

  568.      * <code>StyleConstants</code> key <code>sc</code>.

  569.      * If no matching <code>Tag</code> is found, returns

  570.      * <code>null</code>.

  571.      *

  572.      * @param sc the <code>StyleConstants</code> key

  573.      * @return tag which corresponds to <code>sc</code>, or

  574.      *   <code>null</code> if not found

  575.      */

  576.     static Tag getTagForStyleConstantsKey(StyleConstants sc) {

  577.         return (Tag)scMapping.get(sc);

  578.     }

  579. 

  580.     /**

  581.      * Fetches an integer attribute value.  Attribute values

  582.      * are stored as a string, and this is a convenience method

  583.      * to convert to an actual integer.

  584.      *

  585.      * @param attr the set of attributes to use to try to fetch a value

  586.      * @param key the key to use to fetch the value

  587.      * @param def the default value to use if the attribute isn't

  588.      *  defined or there is an error converting to an integer

  589.      */

  590.     public static int getIntegerAttributeValue(AttributeSet attr,

  591. 					       Attribute key, int def) {

  592. 	int value = def;

  593. 	String istr = (String) attr.getAttribute(key);

  594. 	if (istr != null) {

  595. 	    try {

  596. 		value = Integer.valueOf(istr).intValue();

  597. 	    } catch (NumberFormatException e) {

  598. 		value = def;

  599. 	    }

  600. 	}

  601. 	return value;

  602.     }

  603. 

  604.     //  This is used in cases where the value for the attribute has not

  605.     //  been specified.

  606.     //

  607.     public static final String NULL_ATTRIBUTE_VALUE = "#DEFAULT";

  608. 

  609.     // size determined similar to size of tagHashtable

  610.     private static final Hashtable attHashtable = new Hashtable(77);

  611. 

  612.     static {

  613. 

  614. 	for (int i = 0; i < Attribute.allAttributes.length; i++ ) {

  615. 	    attHashtable.put(Attribute.allAttributes[i].toString(), Attribute.allAttributes[i]);

  616. 	}

  617.     }

  618. 

  619.     /**

  620.      * Returns the set of HTML attributes recognized.

  621.      * @return the set of HTML attributes recognized

  622.      */

  623.     public static Attribute[] getAllAttributeKeys() {

  624. 	Attribute[] attributes = new Attribute[Attribute.allAttributes.length];

  625. 	System.arraycopy(Attribute.allAttributes, 0, 

  626. 			 attributes, 0, Attribute.allAttributes.length);

  627. 	return attributes;

  628.     }

  629. 

  630.     /**

  631.      * Fetches an attribute constant for a well-known attribute name

  632.      * (i.e. one of the attributes in the set {FACE, COMMENT, SIZE,

  633.      * COLOR, CLEAR, BACKGROUND, BGCOLOR, TEXT, LINK, VLINK, ALINK,

  634.      * WIDTH, HEIGHT, ALIGN, NAME, HREF, REL, REV, TITLE, TARGET,

  635.      * SHAPE, COORDS, ISMAP, NOHREF, ALT, ID, SRC, HSPACE, VSPACE,

  636.      * USEMAP, LOWSRC, CODEBASE, CODE, ARCHIVE, VALUE, VALUETYPE,

  637.      * TYPE, CLASS, STYLE, LANG, DIR, DECLARE, CLASSID, DATA, CODETYPE,

  638.      * STANDBY, BORDER, SHAPES, NOSHADE, COMPACT, START, ACTION, METHOD,

  639.      * ENCTYPE, CHECKED, MAXLENGTH, MULTIPLE, SELECTED, ROWS, COLS,

  640.      * DUMMY, CELLSPACING, CELLPADDING, VALIGN, HALIGN, NOWRAP, ROWSPAN,

  641.      * COLSPAN, PROMPT, HTTPEQUIV, CONTENT, LANGUAGE, VERSION, N,

  642.      * FRAMEBORDER, MARGINWIDTH, MARGINHEIGHT, SCROLLING, NORESIZE,

  643.      * MEDIA, ENDTAG}).

  644.      * If the given name does not represent one of the well-known attributes,

  645.      * then <code>null</code> will be returned.

  646.      *

  647.      * @param attName the <code>String</code> requested

  648.      * @return the <code>Attribute</code> corresponding to <code>attName</code>

  649.      */

  650.     public static Attribute getAttributeKey(String attName) {

  651. 	Object a = attHashtable.get(attName);

  652. 	if (a == null) {

  653. 	  return null;

  654. 	}

  655. 	return (Attribute)a;

  656.     }

  657. 

  658. }