HTML.java

/*
 * Copyright (c) 1998, 2025, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation. Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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packagejavax.swing.text.html;

importjava.io.IOException;
importjava.io.ObjectInputStream;
importjava.io.Serial;
importjava.io.Serializable;
importjava.util.Hashtable;
importjava.util.Map;

importjavax.swing.text.AttributeSet;
importjavax.swing.text.StyleConstants;
importjavax.swing.text.StyleContext;

/**
 * Constants used in the <code>HTMLDocument</code>. These
 * are basically tag and attribute definitions.
 *
 * @author Timothy Prinzing
 * @author Sunita Mani
 *
 */
publicclassHTML {

/**
 * Constructs a {@code HTML}.
 */
publicHTML() {}

/**
 * Typesafe enumeration for an HTML tag. Although the
 * set of HTML tags is a closed set, we have left the
 * set open so that people can add their own tag types
 * to their custom parser and still communicate to the
 * reader.
 */
publicstaticclassTag {

/**
 * Constructs a {@code Tag}.
 *
 * @since 1.3
 */
publicTag() {}

/**
 * Creates a new <code>Tag</code> with the specified <code>id</code>,
 * and with <code>causesBreak</code> and <code>isBlock</code>
 * set to <code>false</code>.
 *
 * @param id the id of the new tag
 */
protectedTag(Stringid) {
this(id, false, false);
 }

/**
 * Creates a new <code>Tag</code> with the specified <code>id</code>;
 * <code>causesBreak</code> and <code>isBlock</code> are defined
 * by the user.
 *
 * @param id the id of the new tag
 * @param causesBreak <code>true</code> if this tag
 * causes a break to the flow of data
 * @param isBlock <code>true</code> if the tag is used
 * to add structure to a document
 */
protectedTag(Stringid, booleancausesBreak, booleanisBlock) {
name = id;
this.breakTag = causesBreak;
this.blockTag = isBlock;
 }

/**
 * Returns <code>true</code> if this tag is a block
 * tag, which is a tag used to add structure to a
 * document.
 *
 * @return <code>true</code> if this tag is a block
 * tag, otherwise returns <code>false</code>
 */
publicbooleanisBlock() {
returnblockTag;
 }

/**
 * Returns <code>true</code> if this tag causes a
 * line break to the flow of data, otherwise returns
 * <code>false</code>.
 *
 * @return <code>true</code> if this tag causes a
 * line break to the flow of data, otherwise returns
 * <code>false</code>
 */
publicbooleanbreaksFlow() {
returnbreakTag;
 }

/**
 * Returns <code>true</code> if this tag is pre-formatted,
 * which is true if the tag is either <code>PRE</code> or
 * <code>TEXTAREA</code>.
 *
 * @return <code>true</code> if this tag is pre-formatted,
 * otherwise returns <code>false</code>
 */
publicbooleanisPreformatted() {
return (this == PRE || this == TEXTAREA);
 }

/**
 * Returns the string representation of the
 * tag.
 *
 * @return the <code>String</code> representation of the tag
 */
publicStringtoString() {
returnname;
 }

/**
 * Returns <code>true</code> if this tag is considered to be a paragraph
 * in the internal HTML model. <code>false</code> - otherwise.
 *
 * @return <code>true</code> if this tag is considered to be a paragraph
 * in the internal HTML model. <code>false</code> - otherwise.
 * @see HTMLDocument.HTMLReader.ParagraphAction
 */
booleanisParagraph() {
return (
this == P
 || this == IMPLIED
 || this == DT
 || this == H1
 || this == H2
 || this == H3
 || this == H4
 || this == H5
 || this == H6
 );
 }

booleanblockTag;
booleanbreakTag;
Stringname;
booleanunknown;

// --- Tag Names -----------------------------------

/**
 * Tag &lt;a&gt;
 */
publicstaticfinalTagA = newTag("a");

/**
 * Tag &lt;address&gt;
 */
publicstaticfinalTagADDRESS = newTag("address");
/**
 * Tag &lt;applet&gt;
 */
publicstaticfinalTagAPPLET = newTag("applet");

/**
 * Tag &lt;area&gt;
 */
publicstaticfinalTagAREA = newTag("area");

/**
 * Tag &lt;b&gt;
 */
publicstaticfinalTagB = newTag("b");

/**
 * Tag &lt;base&gt;
 */
publicstaticfinalTagBASE = newTag("base");

/**
 * Tag &lt;basefont&gt;
 */
publicstaticfinalTagBASEFONT = newTag("basefont");

/**
 * Tag &lt;big&gt;
 */
publicstaticfinalTagBIG = newTag("big");

/**
 * Tag &lt;blockquote&gt;
 */
publicstaticfinalTagBLOCKQUOTE = newTag("blockquote", true, true);

/**
 * Tag &lt;body&gt;
 */
publicstaticfinalTagBODY = newTag("body", true, true);

/**
 * Tag &lt;br&gt;
 */
publicstaticfinalTagBR = newTag("br", true, false);

/**
 * Tag &lt;caption&gt;
 */
publicstaticfinalTagCAPTION = newTag("caption");

/**
 * Tag &lt;center&gt;
 */
publicstaticfinalTagCENTER = newTag("center", true, false);

/**
 * Tag &lt;cite&gt;
 */
publicstaticfinalTagCITE = newTag("cite");

/**
 * Tag &lt;code&gt;
 */
publicstaticfinalTagCODE = newTag("code");

/**
 * Tag &lt;dd&gt;
 */
publicstaticfinalTagDD = newTag("dd", true, true);

/**
 * Tag &lt;dfn&gt;
 */
publicstaticfinalTagDFN = newTag("dfn");

/**
 * Tag &lt;dir&gt;
 */
publicstaticfinalTagDIR = newTag("dir", true, true);

/**
 * Tag &lt;div&gt;
 */
publicstaticfinalTagDIV = newTag("div", true, true);

/**
 * Tag &lt;dl&gt;
 */
publicstaticfinalTagDL = newTag("dl", true, true);

/**
 * Tag &lt;dt&gt;
 */
publicstaticfinalTagDT = newTag("dt", true, true);

/**
 * Tag &lt;em&gt;
 */
publicstaticfinalTagEM = newTag("em");

/**
 * Tag &lt;font&gt;
 */
publicstaticfinalTagFONT = newTag("font");

/**
 * Tag &lt;form&gt;
 */
publicstaticfinalTagFORM = newTag("form", true, false);

/**
 * Tag &lt;frame&gt;
 */
publicstaticfinalTagFRAME = newTag("frame");

/**
 * Tag &lt;frameset&gt;
 */
publicstaticfinalTagFRAMESET = newTag("frameset");

/**
 * Tag &lt;h1&gt;
 */
publicstaticfinalTagH1 = newTag("h1", true, true);

/**
 * Tag &lt;h2&gt;
 */
publicstaticfinalTagH2 = newTag("h2", true, true);

/**
 * Tag &lt;h3&gt;
 */
publicstaticfinalTagH3 = newTag("h3", true, true);

/**
 * Tag &lt;h4&gt;
 */
publicstaticfinalTagH4 = newTag("h4", true, true);

/**
 * Tag &lt;h5&gt;
 */
publicstaticfinalTagH5 = newTag("h5", true, true);

/**
 * Tag &lt;h6&gt;
 */
publicstaticfinalTagH6 = newTag("h6", true, true);

/**
 * Tag &lt;head&gt;
 */
publicstaticfinalTagHEAD = newTag("head", true, true);

/**
 * Tag &lt;hr&gt;
 */
publicstaticfinalTagHR = newTag("hr", true, false);

/**
 * Tag &lt;html&gt;
 */
publicstaticfinalTagHTML = newTag("html", true, false);

/**
 * Tag &lt;i&gt;
 */
publicstaticfinalTagI = newTag("i");

/**
 * Tag &lt;img&gt;
 */
publicstaticfinalTagIMG = newTag("img");

/**
 * Tag &lt;input&gt;
 */
publicstaticfinalTagINPUT = newTag("input");

/**
 * Tag &lt;isindex&gt;
 */
publicstaticfinalTagISINDEX = newTag("isindex", true, false);

/**
 * Tag &lt;kbd&gt;
 */
publicstaticfinalTagKBD = newTag("kbd");

/**
 * Tag &lt;li&gt;
 */
publicstaticfinalTagLI = newTag("li", true, true);

/**
 * Tag &lt;link&gt;
 */
publicstaticfinalTagLINK = newTag("link");

/**
 * Tag &lt;map&gt;
 */
publicstaticfinalTagMAP = newTag("map");

/**
 * Tag &lt;menu&gt;
 */
publicstaticfinalTagMENU = newTag("menu", true, true);

/**
 * Tag &lt;meta&gt;
 */
publicstaticfinalTagMETA = newTag("meta");
/*public*/staticfinalTagNOBR = newTag("nobr");

/**
 * Tag &lt;noframes&gt;
 */
publicstaticfinalTagNOFRAMES = newTag("noframes", true, true);

/**
 * Tag &lt;object&gt;
 */
publicstaticfinalTagOBJECT = newTag("object");

/**
 * Tag &lt;ol&gt;
 */
publicstaticfinalTagOL = newTag("ol", true, true);

/**
 * Tag &lt;option&gt;
 */
publicstaticfinalTagOPTION = newTag("option");

/**
 * Tag &lt;p&gt;
 */
publicstaticfinalTagP = newTag("p", true, true);

/**
 * Tag &lt;param&gt;
 */
publicstaticfinalTagPARAM = newTag("param");

/**
 * Tag &lt;pre&gt;
 */
publicstaticfinalTagPRE = newTag("pre", true, true);

/**
 * Tag &lt;samp&gt;
 */
publicstaticfinalTagSAMP = newTag("samp");

/**
 * Tag &lt;script&gt;
 */
publicstaticfinalTagSCRIPT = newTag("script");

/**
 * Tag &lt;select&gt;
 */
publicstaticfinalTagSELECT = newTag("select");

/**
 * Tag &lt;small&gt;
 */
publicstaticfinalTagSMALL = newTag("small");

/**
 * Tag &lt;span&gt;
 */
publicstaticfinalTagSPAN = newTag("span");

/**
 * Tag &lt;strike&gt;
 */
publicstaticfinalTagSTRIKE = newTag("strike");

/**
 * Tag &lt;s&gt;
 */
publicstaticfinalTagS = newTag("s");

/**
 * Tag &lt;strong&gt;
 */
publicstaticfinalTagSTRONG = newTag("strong");

/**
 * Tag &lt;style&gt;
 */
publicstaticfinalTagSTYLE = newTag("style");

/**
 * Tag &lt;sub&gt;
 */
publicstaticfinalTagSUB = newTag("sub");

/**
 * Tag &lt;sup&gt;
 */
publicstaticfinalTagSUP = newTag("sup");

/**
 * Tag &lt;table&gt;
 */
publicstaticfinalTagTABLE = newTag("table", false, true);

/**
 * Tag &lt;td&gt;
 */
publicstaticfinalTagTD = newTag("td", true, true);

/**
 * Tag &lt;textarea&gt;
 */
publicstaticfinalTagTEXTAREA = newTag("textarea");

/**
 * Tag &lt;th&gt;
 */
publicstaticfinalTagTH = newTag("th", true, true);

/**
 * Tag &lt;title&gt;
 */
publicstaticfinalTagTITLE = newTag("title", true, true);

/**
 * Tag &lt;tr&gt;
 */
publicstaticfinalTagTR = newTag("tr", false, true);

/**
 * Tag &lt;tt&gt;
 */
publicstaticfinalTagTT = newTag("tt");

/**
 * Tag &lt;u&gt;
 */
publicstaticfinalTagU = newTag("u");

/**
 * Tag &lt;ul&gt;
 */
publicstaticfinalTagUL = newTag("ul", true, true);

/**
 * Tag &lt;var&gt;
 */
publicstaticfinalTagVAR = newTag("var");

/**
 * All text content must be in a paragraph element.
 * If a paragraph didn't exist when content was
 * encountered, a paragraph is manufactured.
 * <p>
 * This is a tag synthesized by the HTML reader.
 * Since elements are identified by their tag type,
 * we create a some fake tag types to mark the elements
 * that were manufactured.
 */
publicstaticfinalTagIMPLIED = newTag("p-implied");

/**
 * All text content is labeled with this tag.
 * <p>
 * This is a tag synthesized by the HTML reader.
 * Since elements are identified by their tag type,
 * we create a some fake tag types to mark the elements
 * that were manufactured.
 */
publicstaticfinalTagCONTENT = newTag("content");

/**
 * All comments are labeled with this tag.
 * <p>
 * This is a tag synthesized by the HTML reader.
 * Since elements are identified by their tag type,
 * we create a some fake tag types to mark the elements
 * that were manufactured.
 */
publicstaticfinalTagCOMMENT = newTag("comment");

staticfinalTag[] allTags = {
A, ADDRESS, APPLET, AREA, B, BASE, BASEFONT, BIG,
BLOCKQUOTE, BODY, BR, CAPTION, CENTER, CITE, CODE,
DD, DFN, DIR, DIV, DL, DT, EM, FONT, FORM, FRAME,
FRAMESET, H1, H2, H3, H4, H5, H6, HEAD, HR, HTML,
I, IMG, INPUT, ISINDEX, KBD, LI, LINK, MAP, MENU,
META, NOBR, NOFRAMES, OBJECT, OL, OPTION, P, PARAM,
PRE, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, S,
STRONG, STYLE, SUB, SUP, TABLE, TD, TEXTAREA,
TH, TITLE, TR, TT, U, UL, VAR
 };

static {
// Force HTMLs static initialize to be loaded.
getTag("html");
 }
 }

/**
 * Class represents unknown HTML tag.
 */
// There is no unique instance of UnknownTag, so we allow it to be
// Serializable.
@SuppressWarnings("serial") // Same-version serialization only
publicstaticclassUnknownTagextendsTagimplementsSerializable {

/**
 * Creates a new <code>UnknownTag</code> with the specified
 * <code>id</code>.
 * @param id the id of the new tag
 */
publicUnknownTag(Stringid) {
super(id);
 }

/**
 * Returns the hash code which corresponds to the string
 * for this tag.
 */
publicinthashCode() {
returntoString().hashCode();
 }

/**
 * Compares this object to the specified object.
 * The result is <code>true</code> if and only if the argument is not
 * <code>null</code> and is an <code>UnknownTag</code> object
 * with the same name.
 *
 * @param obj the object to compare this tag with
 * @return <code>true</code> if the objects are equal;
 * <code>false</code> otherwise
 */
publicbooleanequals(Objectobj) {
if (objinstanceofUnknownTag) {
returntoString().equals(obj.toString());
 }
returnfalse;
 }

@Serial
privatevoidwriteObject(java.io.ObjectOutputStreams)
throwsIOException {
s.defaultWriteObject();
s.writeBoolean(blockTag);
s.writeBoolean(breakTag);
s.writeBoolean(unknown);
s.writeObject(name);
 }

@Serial
privatevoidreadObject(ObjectInputStreams)
throwsClassNotFoundException, IOException {
s.defaultReadObject();
blockTag = s.readBoolean();
breakTag = s.readBoolean();
unknown = s.readBoolean();
name = (String)s.readObject();
 }
 }

/**
 * Typesafe enumeration representing an HTML
 * attribute.
 */
publicstaticfinalclassAttribute {

/**
 * Creates a new <code>Attribute</code> with the specified
 * <code>id</code>.
 *
 * @param id the id of the new <code>Attribute</code>
 */
Attribute(Stringid) {
name = id;
 }

/**
 * Returns the string representation of this attribute.
 * @return the string representation of this attribute
 */
publicStringtoString() {
returnname;
 }

privateStringname;


/**
 * Attribute "size"
 */
publicstaticfinalAttributeSIZE = newAttribute("size");

/**
 * Attribute "color"
 */
publicstaticfinalAttributeCOLOR = newAttribute("color");

/**
 * Attribute "clear"
 */
publicstaticfinalAttributeCLEAR = newAttribute("clear");

/**
 * Attribute "background"
 */
publicstaticfinalAttributeBACKGROUND = newAttribute("background");

/**
 * Attribute "bgcolor"
 */
publicstaticfinalAttributeBGCOLOR = newAttribute("bgcolor");

/**
 * Attribute "text"
 */
publicstaticfinalAttributeTEXT = newAttribute("text");

/**
 * Attribute "link"
 */
publicstaticfinalAttributeLINK = newAttribute("link");

/**
 * Attribute "vlink"
 */
publicstaticfinalAttributeVLINK = newAttribute("vlink");

/**
 * Attribute "alink"
 */
publicstaticfinalAttributeALINK = newAttribute("alink");

/**
 * Attribute "width"
 */
publicstaticfinalAttributeWIDTH = newAttribute("width");

/**
 * Attribute "height"
 */
publicstaticfinalAttributeHEIGHT = newAttribute("height");

/**
 * Attribute "align"
 */
publicstaticfinalAttributeALIGN = newAttribute("align");

/**
 * Attribute "name"
 */
publicstaticfinalAttributeNAME = newAttribute("name");

/**
 * Attribute "href"
 */
publicstaticfinalAttributeHREF = newAttribute("href");

/**
 * Attribute "rel"
 */
publicstaticfinalAttributeREL = newAttribute("rel");

/**
 * Attribute "rev"
 */
publicstaticfinalAttributeREV = newAttribute("rev");

/**
 * Attribute "title"
 */
publicstaticfinalAttributeTITLE = newAttribute("title");

/**
 * Attribute "target"
 */
publicstaticfinalAttributeTARGET = newAttribute("target");

/**
 * Attribute "shape"
 */
publicstaticfinalAttributeSHAPE = newAttribute("shape");

/**
 * Attribute "coords"
 */
publicstaticfinalAttributeCOORDS = newAttribute("coords");

/**
 * Attribute "ismap"
 */
publicstaticfinalAttributeISMAP = newAttribute("ismap");

/**
 * Attribute "nohref"
 */
publicstaticfinalAttributeNOHREF = newAttribute("nohref");

/**
 * Attribute "alt"
 */
publicstaticfinalAttributeALT = newAttribute("alt");

/**
 * Attribute "id"
 */
publicstaticfinalAttributeID = newAttribute("id");

/**
 * Attribute "src"
 */
publicstaticfinalAttributeSRC = newAttribute("src");

/**
 * Attribute "hspace"
 */
publicstaticfinalAttributeHSPACE = newAttribute("hspace");

/**
 * Attribute "vspace"
 */
publicstaticfinalAttributeVSPACE = newAttribute("vspace");

/**
 * Attribute "usemap"
 */
publicstaticfinalAttributeUSEMAP = newAttribute("usemap");

/**
 * Attribute "lowsrc"
 */
publicstaticfinalAttributeLOWSRC = newAttribute("lowsrc");

/**
 * Attribute "codebase"
 */
publicstaticfinalAttributeCODEBASE = newAttribute("codebase");

/**
 * Attribute "code"
 */
publicstaticfinalAttributeCODE = newAttribute("code");

/**
 * Attribute "archive"
 */
publicstaticfinalAttributeARCHIVE = newAttribute("archive");

/**
 * Attribute "value"
 */
publicstaticfinalAttributeVALUE = newAttribute("value");

/**
 * Attribute "valuetype"
 */
publicstaticfinalAttributeVALUETYPE = newAttribute("valuetype");

/**
 * Attribute "type"
 */
publicstaticfinalAttributeTYPE = newAttribute("type");

/**
 * Attribute "class"
 */
publicstaticfinalAttributeCLASS = newAttribute("class");

/**
 * Attribute "style"
 */
publicstaticfinalAttributeSTYLE = newAttribute("style");

/**
 * Attribute "lang"
 */
publicstaticfinalAttributeLANG = newAttribute("lang");

/**
 * Attribute "face"
 */
publicstaticfinalAttributeFACE = newAttribute("face");

/**
 * Attribute "dir"
 */
publicstaticfinalAttributeDIR = newAttribute("dir");

/**
 * Attribute "declare"
 */
publicstaticfinalAttributeDECLARE = newAttribute("declare");

/**
 * Attribute "classid"
 */
publicstaticfinalAttributeCLASSID = newAttribute("classid");

/**
 * Attribute "data"
 */
publicstaticfinalAttributeDATA = newAttribute("data");

/**
 * Attribute "codetype"
 */
publicstaticfinalAttributeCODETYPE = newAttribute("codetype");

/**
 * Attribute "standby"
 */
publicstaticfinalAttributeSTANDBY = newAttribute("standby");

/**
 * Attribute "border"
 */
publicstaticfinalAttributeBORDER = newAttribute("border");

/**
 * Attribute "shapes"
 */
publicstaticfinalAttributeSHAPES = newAttribute("shapes");

/**
 * Attribute "noshade"
 */
publicstaticfinalAttributeNOSHADE = newAttribute("noshade");

/**
 * Attribute "compact"
 */
publicstaticfinalAttributeCOMPACT = newAttribute("compact");

/**
 * Attribute "start"
 */
publicstaticfinalAttributeSTART = newAttribute("start");

/**
 * Attribute "action"
 */
publicstaticfinalAttributeACTION = newAttribute("action");

/**
 * Attribute "method"
 */
publicstaticfinalAttributeMETHOD = newAttribute("method");

/**
 * Attribute "enctype"
 */
publicstaticfinalAttributeENCTYPE = newAttribute("enctype");

/**
 * Attribute "checked"
 */
publicstaticfinalAttributeCHECKED = newAttribute("checked");

/**
 * Attribute "maxlength"
 */
publicstaticfinalAttributeMAXLENGTH = newAttribute("maxlength");

/**
 * Attribute "multiple"
 */
publicstaticfinalAttributeMULTIPLE = newAttribute("multiple");

/**
 * Attribute "selected"
 */
publicstaticfinalAttributeSELECTED = newAttribute("selected");

/**
 * Attribute "rows"
 */
publicstaticfinalAttributeROWS = newAttribute("rows");

/**
 * Attribute "cols"
 */
publicstaticfinalAttributeCOLS = newAttribute("cols");

/**
 * Attribute "dummy"
 */
publicstaticfinalAttributeDUMMY = newAttribute("dummy");

/**
 * Attribute "cellspacing"
 */
publicstaticfinalAttributeCELLSPACING = newAttribute("cellspacing");

/**
 * Attribute "cellpadding"
 */
publicstaticfinalAttributeCELLPADDING = newAttribute("cellpadding");

/**
 * Attribute "valign"
 */
publicstaticfinalAttributeVALIGN = newAttribute("valign");

/**
 * Attribute "halign"
 */
publicstaticfinalAttributeHALIGN = newAttribute("halign");

/**
 * Attribute "nowrap"