com.thoughtworks.xstream.io.xml

Class SaxWriter

java.lang.Object

com.thoughtworks.xstream.io.AbstractWriter

com.thoughtworks.xstream.io.xml.AbstractXmlWriter

com.thoughtworks.xstream.io.xml.SaxWriter

All Implemented Interfaces:

ExtendedHierarchicalStreamWriter, HierarchicalStreamWriter, XmlFriendlyWriter, XMLReader

public final class SaxWriter
extends AbstractXmlWriter
implements XMLReader

A SAX parser that acts as an XStream HierarchicalStreamWriter to enable direct generation of a SAX event flow from the XStream serialization of a list of list of Java objects.

As a custom SAX parser, this class ignores the arguments of the two standard parse methods (parse(java.lang.String) and parse(org.xml.sax.InputSource)) but relies on a proprietary SAX property SOURCE_OBJECT_LIST_PROPERTY to define the list of objects to serialize.

Configuration of this SAX parser is achieved through the standard SAX property mechanism. While specific setter methods require direct access to the parser instance, SAX properties support configuration settings to be propagated through a chain of filters down to the underlying parser object.

This mechanism shall be used to configure the objects to be serialized as well as the XStream facade.

Author:

Laurent Bihanic

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONFIGURED_XSTREAM_PROPERTY The SAX property to configure the XStream facade to be used for object serialization.
static String	SOURCE_OBJECT_LIST_PROPERTY The SAX property to configure the list of Java objects to serialize.

Constructor Summary

Constructors

Constructor and Description
SaxWriter()
SaxWriter(boolean includeEnclosingDocument)
SaxWriter(boolean includeEnclosingDocument, NameCoder nameCoder)
SaxWriter(boolean includeEnclosingDocument, XmlFriendlyReplacer replacer) Deprecated. As of 1.4 use SaxWriter(boolean, NameCoder) instead.
SaxWriter(NameCoder nameCoder)
SaxWriter(XmlFriendlyReplacer replacer) Deprecated. As of 1.4 use SaxWriter(NameCoder) instead.

Method Summary

Modifier and Type	Method and Description
void	addAttribute(String name, String value)
void	close() Close the writer, if necessary.
void	endNode()
void	flush() Flush the writer, if necessary.
ContentHandler	getContentHandler() Returns the current content handler.
DTDHandler	getDTDHandler() Returns the current DTD handler.
EntityResolver	getEntityResolver() Returns the current entity resolver.
ErrorHandler	getErrorHandler() Returns the current error handler.
boolean	getFeature(String name) Looks up the value of a feature.
Object	getProperty(String name) Looks up the value of a property.
void	parse(InputSource input) Parse an XML document.
void	parse(String systemId) Parses an XML document from a system identifier (URI).
void	setContentHandler(ContentHandler handler) Allows an application to register a content event handler.
void	setDTDHandler(DTDHandler handler) Allows an application to register a DTD event handler.
void	setEntityResolver(EntityResolver resolver) Allows an application to register an entity resolver.
void	setErrorHandler(ErrorHandler handler) Allows an application to register an error event handler.
void	setFeature(String name, boolean value) Sets the state of a feature.
void	setProperty(String name, Object value) Sets the value of a property.
void	setValue(String text) Write the value (text content) of the current node.
void	startNode(String name)

Methods inherited from class com.thoughtworks.xstream.io.xml.AbstractXmlWriter

escapeXmlName

Methods inherited from class com.thoughtworks.xstream.io.AbstractWriter

encodeAttribute, encodeNode, startNode, underlyingWriter

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

CONFIGURED_XSTREAM_PROPERTY

public static final String CONFIGURED_XSTREAM_PROPERTY

The SAX property to configure the XStream facade to be used for object serialization. If the property is not set, a new XStream facade will be allocated for each parse.

See Also:

Constant Field Values

SOURCE_OBJECT_LIST_PROPERTY

public static final String SOURCE_OBJECT_LIST_PROPERTY

The SAX property to configure the list of Java objects to serialize. Setting this property prior invoking one of the parse() methods is mandatory.

See Also:

parse(java.lang.String), parse(org.xml.sax.InputSource), Constant Field Values

Constructor Detail

SaxWriter

public SaxWriter(NameCoder nameCoder)

Since:

1.4

SaxWriter

public SaxWriter(boolean includeEnclosingDocument,
                 NameCoder nameCoder)

Since:

1.4

SaxWriter

public SaxWriter(XmlFriendlyReplacer replacer)

Deprecated. As of 1.4 use SaxWriter(NameCoder) instead.

SaxWriter

public SaxWriter(boolean includeEnclosingDocument,
                 XmlFriendlyReplacer replacer)

Deprecated. As of 1.4 use SaxWriter(boolean, NameCoder) instead.

SaxWriter

public SaxWriter(boolean includeEnclosingDocument)

SaxWriter

public SaxWriter()

Method Detail

setFeature

public void setFeature(String name,
                       boolean value)
                throws SAXNotRecognizedException

Sets the state of a feature.

The feature name is any fully-qualified URI.

All XMLReaders are required to support setting http://xml.org/sax/features/namespaces to true and http://xml.org/sax/features/namespace-prefixes to false.

Some feature values may be immutable or mutable only in specific contexts, such as before, during, or after a parse.

Note: This implementation only supports the two mandatory SAX features.

Specified by:

setFeature in interface XMLReader

Parameters:

name - the feature name, which is a fully-qualified URI.

value - the requested state of the feature (true or false).

Throws:

SAXNotRecognizedException - when the XMLReader does not recognize the feature name.

See Also:

getFeature(java.lang.String)

getFeature

public boolean getFeature(String name)
                   throws SAXNotRecognizedException

Looks up the value of a feature.

The feature name is any fully-qualified URI. It is possible for an XMLReader to recognize a feature name but to be unable to return its value; this is especially true in the case of an adapter for a SAX1 Parser, which has no way of knowing whether the underlying parser is performing validation or expanding external entities.

All XMLReaders are required to recognize the http://xml.org/sax/features/namespaces and the http://xml.org/sax/features/namespace-prefixes feature names.

Some feature values may be available only in specific contexts, such as before, during, or after a parse.

Implementors are free (and encouraged) to invent their own features, using names built on their own URIs.

Specified by:

getFeature in interface XMLReader

Parameters:

name - the feature name, which is a fully-qualified URI.

Returns:

the current state of the feature (true or false).

Throws:

SAXNotRecognizedException - when the XMLReader does not recognize the feature name.

See Also:

setFeature(java.lang.String, boolean)

setProperty

public void setProperty(String name,
                        Object value)
                 throws SAXNotRecognizedException,
                        SAXNotSupportedException

Sets the value of a property.

The property name is any fully-qualified URI. It is possible for an XMLReader to recognize a property name but to be unable to set its value.

XMLReaders are not required to recognize setting any specific property names, though a core set is provided with SAX2.

Some property values may be immutable or mutable only in specific contexts, such as before, during, or after a parse.

This method is also the standard mechanism for setting extended handlers.

Note: This implementation only supports two (proprietary) properties: CONFIGURED_XSTREAM_PROPERTY and SOURCE_OBJECT_LIST_PROPERTY.

Specified by:

setProperty in interface XMLReader

Parameters:

name - the property name, which is a fully-qualified URI.

value - the requested value for the property.

Throws:

SAXNotRecognizedException - when the XMLReader does not recognize the property name.

SAXNotSupportedException - when the XMLReader recognizes the property name but cannot set the requested value.

See Also:

getProperty(java.lang.String)

getProperty

public Object getProperty(String name)
                   throws SAXNotRecognizedException

Looks up the value of a property.

The property name is any fully-qualified URI. It is possible for an XMLReader to recognize a property name but to be unable to return its state.

XMLReaders are not required to recognize any specific property names, though an initial core set is documented for SAX2.

Some property values may be available only in specific contexts, such as before, during, or after a parse.

Implementors are free (and encouraged) to invent their own properties, using names built on their own URIs.

Specified by:

getProperty in interface XMLReader

Parameters:

name - the property name, which is a fully-qualified URI.

Returns:

the current value of the property.

Throws:

SAXNotRecognizedException - when the XMLReader does not recognize the property name.

See Also:

getProperty(java.lang.String)

setEntityResolver

public void setEntityResolver(EntityResolver resolver)

Allows an application to register an entity resolver.

If the application does not register an entity resolver, the XMLReader will perform its own default resolution.

Applications may register a new or different resolver in the middle of a parse, and the SAX parser must begin using the new resolver immediately.

Specified by:

setEntityResolver in interface XMLReader

Parameters:

resolver - the entity resolver.

Throws:

NullPointerException - if the resolver argument is null.

See Also:

getEntityResolver()

getEntityResolver

public EntityResolver getEntityResolver()

Returns the current entity resolver.

Specified by:

getEntityResolver in interface XMLReader

Returns:

the current entity resolver, or null if none has been registered.

See Also:

setEntityResolver(org.xml.sax.EntityResolver)

setDTDHandler

public void setDTDHandler(DTDHandler handler)

Allows an application to register a DTD event handler.

If the application does not register a DTD handler, all DTD events reported by the SAX parser will be silently ignored.

Applications may register a new or different handler in the middle of a parse, and the SAX parser must begin using the new handler immediately.

Specified by:

setDTDHandler in interface XMLReader

Parameters:

handler - the DTD handler.

Throws:

NullPointerException - if the handler argument is null.

See Also:

getDTDHandler()

getDTDHandler

public DTDHandler getDTDHandler()

Returns the current DTD handler.

Specified by:

getDTDHandler in interface XMLReader

Returns:

the current DTD handler, or null if none has been registered.

See Also:

setDTDHandler(org.xml.sax.DTDHandler)

setContentHandler

public void setContentHandler(ContentHandler handler)

Allows an application to register a content event handler.

If the application does not register a content handler, all content events reported by the SAX parser will be silently ignored.

Applications may register a new or different handler in the middle of a parse, and the SAX parser must begin using the new handler immediately.

Specified by:

setContentHandler in interface XMLReader

Parameters:

handler - the content handler.

Throws:

NullPointerException - if the handler argument is null.

See Also:

getContentHandler()

getContentHandler

public ContentHandler getContentHandler()

Returns the current content handler.

Specified by:

getContentHandler in interface XMLReader

Returns:

the current content handler, or null if none has been registered.

See Also:

setContentHandler(org.xml.sax.ContentHandler)

setErrorHandler

public void setErrorHandler(ErrorHandler handler)

Allows an application to register an error event handler.

If the application does not register an error handler, all error events reported by the SAX parser will be silently ignored; however, normal processing may not continue. It is highly recommended that all SAX applications implement an error handler to avoid unexpected bugs.

Applications may register a new or different handler in the middle of a parse, and the SAX parser must begin using the new handler immediately.

Specified by:

setErrorHandler in interface XMLReader

Parameters:

handler - the error handler.

Throws:

NullPointerException - if the handler argument is null.

See Also:

getErrorHandler()

getErrorHandler

public ErrorHandler getErrorHandler()

Returns the current error handler.

Specified by:

getErrorHandler in interface XMLReader

Returns:

the current error handler, or null if none has been registered.

See Also:

setErrorHandler(org.xml.sax.ErrorHandler)

parse

public void parse(String systemId)
           throws SAXException

Parses an XML document from a system identifier (URI).

This method is a shortcut for the common case of reading a document from a system identifier. It is the exact equivalent of the following:

    parse(new InputSource(systemId));
  

If the system identifier is a URL, it must be fully resolved by the application before it is passed to the parser.

Note: As a custom SAX parser, this class ignores the systemId argument of this method and relies on the proprietary SAX property SOURCE_OBJECT_LIST_PROPERTY) to define the list of objects to serialize.

Specified by:

parse in interface XMLReader

Parameters:

systemId - the system identifier (URI).

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

parse(org.xml.sax.InputSource)

parse

public void parse(InputSource input)
           throws SAXException

Parse an XML document.

The application can use this method to instruct the XML reader to begin parsing an XML document from any valid input source (a character stream, a byte stream, or a URI).

Applications may not invoke this method while a parse is in progress (they should create a new XMLReader instead for each nested XML document). Once a parse is complete, an application may reuse the same XMLReader object, possibly with a different input source.

During the parse, the XMLReader will provide information about the XML document through the registered event handlers.

This method is synchronous: it will not return until parsing has ended. If a client application wants to terminate parsing early, it should throw an exception.

Note: As a custom SAX parser, this class ignores the source argument of this method and relies on the proprietary SAX property SOURCE_OBJECT_LIST_PROPERTY) to define the list of objects to serialize.

Specified by:

parse in interface XMLReader

Parameters:

input - The input source for the top-level of the XML document.

Throws:

SAXException - Any SAX exception, possibly wrapping another exception.

See Also:

InputSource, parse(java.lang.String), setEntityResolver(org.xml.sax.EntityResolver), setDTDHandler(org.xml.sax.DTDHandler), setContentHandler(org.xml.sax.ContentHandler), setErrorHandler(org.xml.sax.ErrorHandler)

startNode

public void startNode(String name)

Specified by:

startNode in interface HierarchicalStreamWriter

addAttribute

public void addAttribute(String name,
                         String value)

Specified by:

addAttribute in interface HierarchicalStreamWriter

setValue

public void setValue(String text)

Description copied from interface: HierarchicalStreamWriter

Write the value (text content) of the current node.

Specified by:

setValue in interface HierarchicalStreamWriter

endNode

public void endNode()

Specified by:

endNode in interface HierarchicalStreamWriter

flush

public void flush()

Description copied from interface: HierarchicalStreamWriter

Flush the writer, if necessary.

Specified by:

flush in interface HierarchicalStreamWriter

close

public void close()

Description copied from interface: HierarchicalStreamWriter

Close the writer, if necessary.

Specified by:

close in interface HierarchicalStreamWriter