Class DocumentParser

java.lang.Object
javax.swing.text.html.parser.Parser
javax.swing.text.html.parser.DocumentParser
All Implemented Interfaces:
DTDConstants
public class DocumentParser extends Parser
A Parser for HTML Documents (actually, you can specify a DTD, but you should really only use this class with the html dtd in swing). Reads an InputStream of HTML and invokes the appropriate methods in the ParserCallback class. This is the default parser used by HTMLEditorKit to parse HTML url's.

This will message the callback for all valid tags, as well as tags that are implied but not explicitly specified. For example, the html string (<p>blah) only has a p tag defined. The callback will see the following methods:

  1. handleStartTag(html, ...)
  2. handleStartTag(head, ...)
  3. handleEndTag(head)
  4. handleStartTag(body, ...)
  5. handleStartTag(p, ...)
  6. handleText(...)
  7. handleEndTag(p)
  8. handleEndTag(body)
  9. handleEndTag(html)
The items in italic are implied, that is, although they were not explicitly specified, to be correct html they should have been present (head isn't necessary, but it is still generated). For tags that are implied, the AttributeSet argument will have a value of Boolean.TRUE for the key HTMLEditorKit.ParserCallback.IMPLIED.

HTML.Attributes defines a type safe enumeration of html attributes. If an attribute key of a tag is defined in HTML.Attribute, the HTML.Attribute will be used as the key, otherwise a String will be used. For example <p foo=bar class=neat> has two attributes. foo is not defined in HTML.Attribute, where as class is, therefore the AttributeSet will have two values in it, HTML.Attribute.CLASS with a String value of 'neat' and the String key 'foo' with a String value of 'bar'.

The position argument will indicate the start of the tag, comment or text. Similar to arrays, the first character in the stream has a position of 0. For tags that are implied the position will indicate the location of the next encountered tag. In the first example, the implied start body and html tags will have the same position as the p tag, and the implied end p, html and body tags will all have the same position.

As html skips whitespace the position for text will be the position of the first valid character, eg in the string '\n\n\nblah' the text 'blah' will have a position of 3, the newlines are skipped.

For attributes that do not have a value, eg in the html string <foo blah> the attribute blah does not have a value, there are two possible values that will be placed in the AttributeSet's value:

  • If the DTD does not contain an definition for the element, or the definition does not have an explicit value then the value in the AttributeSet will be HTML.NULL_ATTRIBUTE_VALUE.
  • If the DTD contains an explicit value, as in: <!ATTLIST OPTION selected (selected) #IMPLIED> this value from the dtd (in this case selected) will be used.

Once the stream has been parsed, the callback is notified of the most likely end of line string. The end of line string will be one of \n, \r or \r\n, which ever is encountered the most in parsing the stream.

  • Field Summary

    Fields declared in class Parser

    dtd, strict
    Modifier and Type
    Field
    Description
    protected DTD
    dtd
    The dtd.
    protected boolean
    strict
    This flag determines whether or not the Parser will be strict in enforcing SGML compatibility.

    Fields declared in interface 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
    Modifier and Type
    Field
    Description
    static final int
    ANY
    The DTD constant corresponds to ANY
    static final int
    CDATA
    The DTD constant corresponds to CDATA
    static final int
    CONREF
    The DTD constant corresponds to CONREF
    static final int
    CURRENT
    The DTD constant corresponds to CURRENT
    static final int
    DEFAULT
    The DTD constant corresponds to DEFAULT
    static final int
    EMPTY
    The DTD constant corresponds to EMPTY
    static final int
    ENDTAG
    The DTD constant corresponds to ENDTAG
    static final int
    ENTITIES
    The DTD constant corresponds to ENTITIES
    static final int
    ENTITY
    The DTD constant corresponds to ENTITY
    static final int
    FIXED
    The DTD constant corresponds to FIXED
    static final int
    GENERAL
    The DTD constant corresponds to GENERAL
    static final int
    ID
    The DTD constant corresponds to ID
    static final int
    IDREF
    The DTD constant corresponds to IDREF
    static final int
    IDREFS
    The DTD constant corresponds to IDREFS
    static final int
    IMPLIED
    The DTD constant corresponds to IMPLIED
    static final int
    MD
    The DTD constant corresponds to MD
    static final int
    MODEL
    The DTD constant corresponds to MODEL
    static final int
    MS
    The DTD constant corresponds to MS
    static final int
    NAME
    The DTD constant corresponds to NAME
    static final int
    NAMES
    The DTD constant corresponds to NAMES
    static final int
    NMTOKEN
    The DTD constant corresponds to NMTOKEN
    static final int
    NMTOKENS
    The DTD constant corresponds to NMTOKENS
    static final int
    NOTATION
    The DTD constant corresponds to NOTATION
    static final int
    NUMBER
    The DTD constant corresponds to NUMBER
    static final int
    NUMBERS
    The DTD constant corresponds to NUMBERS
    static final int
    NUTOKEN
    The DTD constant corresponds to NUTOKEN
    static final int
    NUTOKENS
    The DTD constant corresponds to NUTOKENS
    static final int
    PARAMETER
    The DTD constant corresponds to PARAMETER
    static final int
    PI
    The DTD constant corresponds to PI
    static final int
    PUBLIC
    The DTD constant corresponds to PUBLIC
    static final int
    RCDATA
    The DTD constant corresponds to RCDATA
    static final int
    REQUIRED
    The DTD constant corresponds to REQUIRED
    static final int
    SDATA
    The DTD constant corresponds to SDATA
    static final int
    STARTTAG
    The DTD constant corresponds to STARTTAG
    static final int
    SYSTEM
    The DTD constant corresponds to SYSTEM

  • Constructor Summary

    Constructors
    Constructor
    Description
    DocumentParser(DTD dtd)
    Creates document parser with the specified dtd.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected void
    handleEmptyTag(TagElement tag)
    Handle Empty Tag.
    protected void
    handleEndTag(TagElement tag)
    Handle End Tag.
    protected void
    handleStartTag(TagElement tag)
    Handle Start Tag.
    protected void
    handleText(char[] data)
    Handle Text.
    void
    parse(Reader in, HTMLEditorKit.ParserCallback callback, boolean ignoreCharSet)
    Parse an HTML stream, given a DTD.

    Methods declared in class Parser

    endTag, error, error, error, error, flushAttributes, getAttributes, getCurrentLine, getCurrentPos, handleComment, handleEOFInComment, handleError, handleTitle, makeTag, makeTag, markFirstTime, parse, parseDTDMarkup, parseMarkupDeclarations, startTag
    Modifier and Type
    Method
    Description
    protected void
    endTag(boolean omitted)
    Handle an end tag.
    protected void
    error(String err)
    Invokes the error handler with the 1st, 2nd and 3rd error message argument "?".
    protected void
    error(String err, String arg1)
    Invokes the error handler with the 2nd and 3rd error message argument "?".
    protected void
    error(String err, String arg1, String arg2)
    Invokes the error handler with the 3rd error message argument "?".
    protected void
    error(String err, String arg1, String arg2, String arg3)
    Invokes the error handler.
    protected void
    flushAttributes()
    Removes the current attributes.
    protected SimpleAttributeSet
    getAttributes()
    Returns attributes for the current tag.
    protected int
    getCurrentLine()
    Returns the line number of the line currently being parsed.
    protected int
    getCurrentPos()
    Returns the current position.
    protected void
    handleComment(char[] text)
    Called when an HTML comment is encountered.
    protected void
    handleEOFInComment()
    Called when the content terminates without closing the HTML comment.
    protected void
    handleError(int ln, String msg)
    An error has occurred.
    protected void
    handleTitle(char[] text)
    Called when an HTML title tag is encountered.
    protected TagElement
    makeTag(Element elem)
    Makes a TagElement.
    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 document
    void
    parse(Reader in)
    Parse an HTML stream, given a DTD.
    String
    parseDTDMarkup()
    Parses the Document Type Declaration markup declaration.
    protected boolean
    parseMarkupDeclarations(StringBuffer strBuff)
    Parse markup declarations.
    protected void
    startTag(TagElement tag)
    Handle a start tag.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Constructor Details

    • DocumentParser

      public DocumentParser(DTD dtd)
      Creates document parser with the specified dtd.
      Parameters:
      dtd - the dtd.

  • Method Details

    • parse

      public void parse(Reader in, HTMLEditorKit.ParserCallback callback, boolean ignoreCharSet) throws IOException
      Parse an HTML stream, given a DTD.
      Parameters:
      in - the reader to read the source from
      callback - the callback
      ignoreCharSet - if true the charset is ignored
      Throws:
      IOException - if an I/O error occurs

    • handleStartTag

      protected void handleStartTag(TagElement tag)
      Handle Start Tag.
      Overrides:
      handleStartTag in class Parser
      Parameters:
      tag - the tag being handled

    • handleEmptyTag

      protected void handleEmptyTag(TagElement tag) throws ChangedCharSetException
      Handle Empty Tag.
      Overrides:
      handleEmptyTag in class Parser
      Parameters:
      tag - the tag being handled
      Throws:
      ChangedCharSetException - if the document charset was changed

    • handleEndTag

      protected void handleEndTag(TagElement tag)
      Handle End Tag.
      Overrides:
      handleEndTag in class Parser
      Parameters:
      tag - the tag being handled

    • handleText

      protected void handleText(char[] data)
      Handle Text.
      Overrides:
      handleText in class Parser
      Parameters:
      data - the section text