package org.jsoup.parser;
import org.jsoup.helper.Validate;
import java.util.HashMap;
import java.util.Map;
/**
* HTML Tag capabilities.
*
* @author Jonathan Hedley, [email protected]
*/
public class Tag {
private static final Map<String, Tag> tags = new HashMap<String, Tag>(); // map of known tags
private String tagName;
private boolean isBlock = true; // block or inline
private boolean formatAsBlock = true; // should be formatted as a block
private boolean canContainBlock = true; // Can this tag hold block level tags?
private boolean canContainInline = true; // only pcdata if not
private boolean empty = false; // can hold nothing; e.g. img
private boolean selfClosing = false; // can self close (<foo />). used for unknown tags that self close, without forcing them as empty.
private boolean preserveWhitespace = false; // for pre, textarea, script etc
private Tag(String tagName) {
this.tagName = tagName.toLowerCase();
}
/**
* Get this tag's name.
*
* @return the tag's name
*/
public String getName() {
return tagName;
}
/**
* Get a Tag by name. If not previously defined (unknown), returns a new generic tag, that can do anything.
* <p/>
* Pre-defined tags (P, DIV etc) will be ==, but unknown tags are not registered and will only .equals().
*
* @param tagName Name of tag, e.g. "p". Case insensitive.
* @return The tag, either defined or new generic.
*/
public static Tag valueOf(String tagName) {
Validate.notNull(tagName);
tagName = tagName.trim().toLowerCase();
Validate.notEmpty(tagName);
synchronized (tags) {
Tag tag = tags.get(tagName);
if (tag == null) {
// not defined: create default; go anywhere, do anything! (incl be inside a <p>)
tag = new Tag(tagName);
tag.isBlock = false;
tag.canContainBlock = true;
}
return tag;
}
}
/**
* Gets if this is a block tag.
*
* @return if block tag
*/
public boolean isBlock() {
return isBlock;
}
/**
* Gets if this tag should be formatted as a block (or as inline)
*
* @return if should be formatted as block or inline
*/
public boolean formatAsBlock() {
return formatAsBlock;
}
/**
* Gets if this tag can contain block tags.
*
* @return if tag can contain block tags
*/
public boolean canContainBlock() {
return canContainBlock;
}
/**
* Gets if this tag is an inline tag.
*
* @return if this tag is an inline tag.
*/
public boolean isInline() {
return !isBlock;
}
/**
* Gets if this tag is a data only tag.
*
* @return if this tag is a data only tag
*/
public boolean isData() {
return !canContainInline && !isEmpty();
}
/**
* Get if this is an empty tag
*
* @return if this is an emtpy tag
*/
public boolean isEmpty() {
return empty;
}
/**
* Get if this tag is self closing.
*
* @return if this tag should be output as self closing.
*/
public boolean isSelfClosing() {
return empty || selfClosing;
}
/**
* Get if this is a pre-defined tag, or was auto created on parsing.
*
* @return if a known tag
*/
public boolean isKnownTag() {
return tags.containsKey(tagName);
}
/**
* Check if this tagname is a known tag.
*
* @param tagName name of tag
* @return if known HTML tag
*/
public static boolean isKnownTag(String tagName) {
return tags.containsKey(tagName);
}
/**
* Get if this tag should preserve whitespace within child text nodes.
*
* @return if preserve whitepace
*/
public boolean preserveWhitespace() {
return preserveWhitespace;
}
Tag setSelfClosing() {
selfClosing = true;
return this;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof Tag)) return false;
Tag tag = (Tag) o;
if (canContainBlock != tag.canContainBlock) return false;
if (canContainInline != tag.canContainInline) return false;
if (empty != tag.empty) return false;
if (formatAsBlock != tag.formatAsBlock) return false;
if (isBlock != tag.isBlock) return false;
if (preserveWhitespace != tag.preserveWhitespace) return false;
if (selfClosing != tag.selfClosing) return false;
if (!tagName.equals(tag.tagName)) return false;
return true;
}
@Override
public int hashCode() {
int result = tagName.hashCode();
result = 31 * result + (isBlock ? 1 : 0);
result = 31 * result + (formatAsBlock ? 1 : 0);
result = 31 * result + (canContainBlock ? 1 : 0);
result = 31 * result + (canContainInline ? 1 : 0);
result = 31 * result + (empty ? 1 : 0);
result = 31 * result + (selfClosing ? 1 : 0);
result = 31 * result + (preserveWhitespace ? 1 : 0);
return result;
}
public String toString() {
return tagName;
}
// internal static initialisers:
// prepped from http://www.w3.org/TR/REC-html40/sgml/dtd.html and other sources
private static final String[] blockTags = {
"html", "head", "body", "frameset", "script", "noscript", "style", "meta", "link", "title", "frame",
"noframes", "section", "nav", "aside", "hgroup", "header", "footer", "p", "h1", "h2", "h3", "h4", "h5", "h6",
"ul", "ol", "pre", "div", "blockquote", "hr", "address", "figure", "figcaption", "form", "fieldset", "ins",
"del", "dl", "dt", "dd", "li", "table", "caption", "thead", "tfoot", "tbody", "colgroup", "col", "tr", "th",
"td", "video", "audio", "canvas", "details", "menu", "plaintext"
};
private static final String[] inlineTags = {
"object", "base", "font", "tt", "i", "b", "u", "big", "small", "em", "strong", "dfn", "code", "samp", "kbd",
"var", "cite", "abbr", "time", "acronym", "mark", "ruby", "rt", "rp", "a", "img", "br", "wbr", "map", "q",
"sub", "sup", "bdo", "iframe", "embed", "span", "input", "select", "textarea", "label", "button", "optgroup",
"option", "legend", "datalist", "keygen", "output", "progress", "meter", "area", "param", "source", "track",
"summary", "command", "device"
};
private static final String[] emptyTags = {
"meta", "link", "base", "frame", "img", "br", "wbr", "embed", "hr", "input", "keygen", "col", "command",
"device"
};
private static final String[] formatAsInlineTags = {
"title", "a", "p", "h1", "h2", "h3", "h4", "h5", "h6", "pre", "address", "li", "th", "td"
};
private static final String[] preserveWhitespaceTags = {"pre", "plaintext", "title"};
static {
// creates
for (String tagName : blockTags) {
Tag tag = new Tag(tagName);
register(tag);
}
for (String tagName : inlineTags) {
Tag tag = new Tag(tagName);
tag.isBlock = false;
tag.canContainBlock = false;
tag.formatAsBlock = false;
register(tag);
}
// mods:
for (String tagName : emptyTags) {
Tag tag = tags.get(tagName);
Validate.notNull(tag);
tag.canContainBlock = false;
tag.canContainInline = false;
tag.empty = true;
}
for (String tagName : formatAsInlineTags) {
Tag tag = tags.get(tagName);
Validate.notNull(tag);
tag.formatAsBlock = false;
}
for (String tagName : preserveWhitespaceTags) {
Tag tag = tags.get(tagName);
Validate.notNull(tag);
tag.preserveWhitespace = true;
}
}
private static Tag register(Tag tag) {
synchronized (tags) {
tags.put(tag.tagName, tag);
}
return tag;
}
}
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