- java.lang.Object
-
- javax.swing.text.html.parser.Parser
-
- All Implemented Interfaces:
- DTDConstants
- Direct Known Subclasses:
- DocumentParser
public class Parser extends Object implements DTDConstants
A simple DTD-driven HTML parser. The parser reads an HTML file from an InputStream and calls various methods (which should be overridden in a subclass) when tags and data are encountered.Unfortunately there are many badly implemented HTML parsers out there, and as a result there are many badly formatted HTML files. This parser attempts to parse most HTML files. This means that the implementation sometimes deviates from the SGML specification in favor of HTML.
The parser treats \r and \r\n as \n. Newlines after starttags and before end tags are ignored just as specified in the SGML/HTML specification.
The html spec does not specify how spaces are to be coalesced very well. Specifically, the following scenarios are not discussed (note that a space should be used here, but I am using   to force the space to be displayed):
'<b>blah <i> <strike> foo' which can be treated as: '<b>blah <i><strike>foo'
as well as: '<p><a href="https://www.gaudry.be/en/java-api-rf-javax/swing/text/html/parser/xx"> <em>Using</em></a></p>' which appears to be treated as: '<p><a href="https://www.gaudry.be/en/java-api-rf-javax/swing/text/html/parser/xx"><em>Using</em></a></p>'
If
strict
is false, when a tag that breaks flow, (TagElement.breaksFlows
) or trailing whitespace is encountered, all whitespace will be ignored until a non whitespace character is encountered. This appears to give behavior closer to the popular browsers.- See Also:
DTD
,TagElement
,SimpleAttributeSet
-
-
Field Summary
Fields Modifier and Type Field and Description protected DTD
dtd
protected boolean
strict
This flag determines whether or not the Parser will be strict in enforcing SGML compatibility.-
Fields inherited from interface javax.swing.text.html.parser.DTDConstants
ANY, CDATA, CONREF, CURRENT, DEFAULT, EMPTY, ENDTAG, ENTITIES, ENTITY, FIXED, GENERAL, ID, IDREF, IDREFS, IMPLIED, MD, MODEL, MS, NAME, NAMES, NMTOKEN, NMTOKENS, NOTATION, NUMBER, NUMBERS, NUTOKEN, NUTOKENS, PARAMETER, PI, PUBLIC, RCDATA, REQUIRED, SDATA, STARTTAG, SYSTEM
-
-
Method Summary
Methods Modifier and Type Method and Description protected void
endTag(boolean omitted)
Handle an end tag.protected void
error(String err)
protected void
error(String err, String arg1)
protected void
error(String err, String arg1, String arg2)
protected void
error(String err, String arg1, String arg2, String arg3)
Invoke the error handler.protected void
flushAttributes()
protected SimpleAttributeSet
getAttributes()
protected int
getCurrentLine()
protected int
getCurrentPos()
protected void
handleComment(char[] text)
Called when an HTML comment is encountered.protected void
handleEmptyTag(TagElement tag)
Called when an empty tag is encountered.protected void
handleEndTag(TagElement tag)
Called when an end tag is encountered.protected void
handleEOFInComment()
protected void
handleError(int ln, String msg)
An error has occurred.protected void
handleStartTag(TagElement tag)
Called when a start tag is encountered.protected void
handleText(char[] text)
Called when PCDATA is encountered.protected void
handleTitle(char[] text)
Called when an HTML title tag is encountered.protected TagElement
makeTag(Element elem)
protected TagElement
makeTag(Element elem, boolean fictional)
Makes a TagElement.protected void
markFirstTime(Element elem)
Marks the first time a tag has been seen in a documentvoid
parse(Reader in)
Parse an HTML stream, given a DTD.String
parseDTDMarkup()
Parses th Document Declaration Type markup declaration.protected boolean
parseMarkupDeclarations(StringBuffer strBuff)
Parse markup declarations.protected void
startTag(TagElement tag)
Handle a start tag.
-
-
-
Field Detail
-
dtd
protected DTD dtd
-
strict
protected boolean strict
This flag determines whether or not the Parser will be strict in enforcing SGML compatibility. If false, it will be lenient with certain common classes of erroneous HTML constructs. Strict or not, in either case an error will be recorded.
-
-
Constructor Detail
-
Parser
public Parser(DTD dtd)
-
-
Method Detail
-
getCurrentLine
protected int getCurrentLine()
- Returns:
- the line number of the line currently being parsed
-
makeTag
protected TagElement makeTag(Element elem, boolean fictional)
Makes a TagElement.
-
makeTag
protected TagElement makeTag(Element elem)
-
getAttributes
protected SimpleAttributeSet getAttributes()
-
flushAttributes
protected void flushAttributes()
-
handleText
protected void handleText(char[] text)
Called when PCDATA is encountered.
-
handleTitle
protected void handleTitle(char[] text)
Called when an HTML title tag is encountered.
-
handleComment
protected void handleComment(char[] text)
Called when an HTML comment is encountered.
-
handleEOFInComment
protected void handleEOFInComment()
-
handleEmptyTag
protected void handleEmptyTag(TagElement tag) throws ChangedCharSetException
Called when an empty tag is encountered.- Throws:
ChangedCharSetException
-
handleStartTag
protected void handleStartTag(TagElement tag)
Called when a start tag is encountered.
-
handleEndTag
protected void handleEndTag(TagElement tag)
Called when an end tag is encountered.
-
handleError
protected void handleError(int ln, String msg)
An error has occurred.
-
error
protected void error(String err, String arg1, String arg2, String arg3)
Invoke the error handler.
-
error
protected void error(String err)
-
startTag
protected void startTag(TagElement tag) throws ChangedCharSetException
Handle a start tag. The new tag is pushed onto the tag stack. The attribute list is checked for required attributes.- Throws:
ChangedCharSetException
-
endTag
protected void endTag(boolean omitted)
Handle an end tag. The end tag is popped from the tag stack.
-
markFirstTime
protected void markFirstTime(Element elem)
Marks the first time a tag has been seen in a document
-
parseDTDMarkup
public String parseDTDMarkup() throws IOException
Parses th Document Declaration Type markup declaration. Currently ignores it.- Throws:
IOException
-
parseMarkupDeclarations
protected boolean parseMarkupDeclarations(StringBuffer strBuff) throws IOException
Parse markup declarations. Currently only handles the Document Type Declaration markup. Returns true if it is a markup declaration false otherwise.- Throws:
IOException
-
parse
public void parse(Reader in) throws IOException
Parse an HTML stream, given a DTD.- Throws:
IOException
-
getCurrentPos
protected int getCurrentPos()
-
-
Document created the 11/06/2005, last modified the 04/03/2020
Source of the printed document:https://www.gaudry.be/en/java-api-rf-javax/swing/text/html/parser/Parser.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.