DefaultHandler2

public class DefaultHandler2 extends DefaultHandler
implements LexicalHandler DeclHandler EntityResolver2

This class extends the SAX2 base handler class to support the SAX2 LexicalHandler, DeclHandler, and EntityResolver2 extensions. Except for overriding the original SAX1 resolveEntity() method the added handler methods just return. Subclassers may override everything on a method-by-method basis.

This module, both source code and documentation, is in the Public Domain, and comes with NO WARRANTY.

Note: this class might yet learn that the ContentHandler.setDocumentLocator() call might be passed a Locator2 object, and that the ContentHandler.startElement() call might be passed a Attributes2 object.

Public Constructor Summary

DefaultHandler2()
Constructs a handler which ignores all parsing events.

Public Method Summary

void
attributeDecl(String eName, String aName, String type, String mode, String value)
Report an attribute type declaration.
void
comment(char[] ch, int start, int length)
Report an XML comment anywhere in the document.
void
elementDecl(String name, String model)
Report an element type declaration.
void
endCDATA()
Report the end of a CDATA section.
void
endDTD()
Report the end of DTD declarations.
void
endEntity(String name)
Report the end of an entity.
void
externalEntityDecl(String name, String publicId, String systemId)
Report a parsed external entity declaration.
InputSource
getExternalSubset(String name, String baseURI)
Tells the parser that if no external subset has been declared in the document text, none should be used.
void
internalEntityDecl(String name, String value)
Report an internal entity declaration.
InputSource
resolveEntity(String publicId, String systemId)
Invokes EntityResolver2.resolveEntity() with null entity name and base URI.
InputSource
resolveEntity(String name, String publicId, String baseURI, String systemId)
Tells the parser to resolve the systemId against the baseURI and read the entity text from that resulting absolute URI.
void
startCDATA()
Report the start of a CDATA section.
void
startDTD(String name, String publicId, String systemId)
Report the start of DTD declarations, if any.
void
startEntity(String name)
Report the beginning of some internal and external XML entities.

Inherited Method Summary

Public Constructors

public DefaultHandler2 ()

Constructs a handler which ignores all parsing events.

Public Methods

public void attributeDecl (String eName, String aName, String type, String mode, String value)

Report an attribute type declaration.

Only the effective (first) declaration for an attribute will be reported. The type will be one of the strings "CDATA", "ID", "IDREF", "IDREFS", "NMTOKEN", "NMTOKENS", "ENTITY", "ENTITIES", a parenthesized token group with the separator "|" and all whitespace removed, or the word "NOTATION" followed by a space followed by a parenthesized token group with all whitespace removed.

The value will be the value as reported to applications, appropriately normalized and with entity and character references expanded.

Parameters
eName The name of the associated element.
aName The name of the attribute.
type A string representing the attribute type.
mode A string representing the attribute defaulting mode ("#IMPLIED", "#REQUIRED", or "#FIXED") or null if none of these applies.
value A string representing the attribute's default value, or null if there is none.
Throws
SAXException

public void comment (char[] ch, int start, int length)

Report an XML comment anywhere in the document.

This callback will be used for comments inside or outside the document element, including comments in the external DTD subset (if read). Comments in the DTD must be properly nested inside start/endDTD and start/endEntity events (if used).

Parameters
ch An array holding the characters in the comment.
start The starting position in the array.
length The number of characters to use from the array.
Throws
SAXException

public void elementDecl (String name, String model)

Report an element type declaration.

The content model will consist of the string "EMPTY", the string "ANY", or a parenthesised group, optionally followed by an occurrence indicator. The model will be normalized so that all parameter entities are fully resolved and all whitespace is removed,and will include the enclosing parentheses. Other normalization (such as removing redundant parentheses or simplifying occurrence indicators) is at the discretion of the parser.

Parameters
name The element type name.
model The content model as a normalized string.
Throws
SAXException

public void endCDATA ()

Report the end of a CDATA section.

Throws
SAXException

public void endDTD ()

Report the end of DTD declarations.

This method is intended to report the end of the DOCTYPE declaration; if the document has no DOCTYPE declaration, this method will not be invoked.

Throws
SAXException

public void endEntity (String name)

Report the end of an entity.

Parameters
name The name of the entity that is ending.
Throws
SAXException

public void externalEntityDecl (String name, String publicId, String systemId)

Report a parsed external entity declaration.

Only the effective (first) declaration for each entity will be reported.

If the system identifier is a URL, the parser must resolve it fully before passing it to the application.

Parameters
name The name of the entity. If it is a parameter entity, the name will begin with '%'.
publicId The entity's public identifier, or null if none was given.
systemId The entity's system identifier.
Throws
SAXException

public InputSource getExternalSubset (String name, String baseURI)

Tells the parser that if no external subset has been declared in the document text, none should be used.

Parameters
name Identifies the document root element. This name comes from a DOCTYPE declaration (where available) or from the actual root element. The parameter is ignored.
baseURI The document's base URI, serving as an additional hint for selecting the external subset. This is always an absolute URI, unless it is null because the XMLReader was given an InputSource without one. The parameter is ignored.
Returns
  • null (always).
Throws
SAXException Any SAX exception, possibly wrapping another exception.
IOException Probably indicating a failure to create a new InputStream or Reader, or an illegal URL.

public void internalEntityDecl (String name, String value)

Report an internal entity declaration.

Only the effective (first) declaration for each entity will be reported. All parameter entities in the value will be expanded, but general entities will not.

Parameters
name The name of the entity. If it is a parameter entity, the name will begin with '%'.
value The replacement text of the entity.
Throws
SAXException

public InputSource resolveEntity (String publicId, String systemId)

Invokes EntityResolver2.resolveEntity() with null entity name and base URI. You only need to override that method to use this class.

Parameters
publicId The public identifier of the external entity being referenced (normalized as required by the XML specification), or null if none was supplied.
systemId The system identifier of the external entity being referenced; either a relative or absolute URI. This is never null when invoked by a SAX2 parser; only declared entities, and any external subset, are resolved by such parsers.
Returns
  • An InputSource object describing the new input source.
Throws
SAXException Any SAX exception, possibly wrapping another exception.
IOException Probably indicating a failure to create a new InputStream or Reader, or an illegal URL.

public InputSource resolveEntity (String name, String publicId, String baseURI, String systemId)

Tells the parser to resolve the systemId against the baseURI and read the entity text from that resulting absolute URI. Note that because the older DefaultHandler.resolveEntity(), method is overridden to call this one, this method may sometimes be invoked with null name and baseURI, and with the systemId already absolutized.

Parameters
name Identifies the external entity being resolved. Either "[dtd]" for the external subset, or a name starting with "%" to indicate a parameter entity, or else the name of a general entity. This is never null when invoked by a SAX2 parser.
publicId The public identifier of the external entity being referenced (normalized as required by the XML specification), or null if none was supplied.
baseURI The URI with respect to which relative systemIDs are interpreted. This is always an absolute URI, unless it is null (likely because the XMLReader was given an InputSource without one). This URI is defined by the XML specification to be the one associated with the "<" starting the relevant declaration.
systemId The system identifier of the external entity being referenced; either a relative or absolute URI. This is never null when invoked by a SAX2 parser; only declared entities, and any external subset, are resolved by such parsers.
Returns
  • An InputSource object describing the new input source.
Throws
SAXException Any SAX exception, possibly wrapping another exception.
IOException Probably indicating a failure to create a new InputStream or Reader, or an illegal URL.

public void startCDATA ()

Report the start of a CDATA section.

The contents of the CDATA section will be reported through the regular characters event; this event is intended only to report the boundary.

Throws
SAXException

public void startDTD (String name, String publicId, String systemId)

Report the start of DTD declarations, if any.

This method is intended to report the beginning of the DOCTYPE declaration; if the document has no DOCTYPE declaration, this method will not be invoked.

All declarations reported through DTDHandler or DeclHandler events must appear between the startDTD and endDTD events. Declarations are assumed to belong to the internal DTD subset unless they appear between startEntity and endEntity events. Comments and processing instructions from the DTD should also be reported between the startDTD and endDTD events, in their original order of (logical) occurrence; they are not required to appear in their correct locations relative to DTDHandler or DeclHandler events, however.

Note that the start/endDTD events will appear within the start/endDocument events from ContentHandler and before the first startElement event.

Parameters
name The document type name.
publicId The declared public identifier for the external DTD subset, or null if none was declared.
systemId The declared system identifier for the external DTD subset, or null if none was declared. (Note that this is not resolved against the document base URI.)
Throws
SAXException

public void startEntity (String name)

Report the beginning of some internal and external XML entities.

The reporting of parameter entities (including the external DTD subset) is optional, and SAX2 drivers that report LexicalHandler events may not implement it; you can use the http://xml.org/sax/features/lexical-handler/parameter-entities feature to query or control the reporting of parameter entities.

General entities are reported with their regular names, parameter entities have '%' prepended to their names, and the external DTD subset has the pseudo-entity name "[dtd]".

When a SAX2 driver is providing these events, all other events must be properly nested within start/end entity events. There is no additional requirement that events from DeclHandler or DTDHandler be properly ordered.

Note that skipped entities will be reported through the skippedEntity event, which is part of the ContentHandler interface.

Because of the streaming event model that SAX uses, some entity boundaries cannot be reported under any circumstances:

  • general entities within attribute values
  • parameter entities within declarations

These will be silently expanded, with no indication of where the original entity boundaries were.

Note also that the boundaries of character references (which are not really entities anyway) are not reported.

All start/endEntity events must be properly nested.

Parameters
name The name of the entity. If it is a parameter entity, the name will begin with '%', and if it is the external DTD subset, it will be "[dtd]".
Throws
SAXException