Package com.stardog.stark.io.rdfxml

Class RDFXMLPrettyWriter

java.lang.Object

com.stardog.stark.io.rdfxml.RDFXMLWriter

com.stardog.stark.io.rdfxml.RDFXMLPrettyWriter

All Implemented Interfaces:

RDFHandler, RDFWriter, java.io.Closeable, java.io.Flushable, java.lang.AutoCloseable

public final class RDFXMLPrettyWriter
extends RDFXMLWriter
implements java.io.Closeable, java.io.Flushable

An extension of RDFXMLWriter that outputs a more concise form of RDF/XML. The resulting output is semantically equivalent to the output of an RDFXMLWriter (it produces the same set of statements), but it is usually easier to read for humans.

This is a quasi-streaming RDFWriter. Statements are cached as long as the striped syntax is followed (i.e. the subject of the next statement is the object of the previous statement) and written to the output when the stripe is broken.

The abbreviations used are typed node elements, empty property elements and striped syntax. Note that these abbreviations require that statements are written in the appropriate order.

Striped syntax means that when the object of a statement is the subject of the next statement we can nest the descriptions in each other.

Example:

 <rdf:Seq>
    <rdf:li>
       <foaf:Person>
          <foaf:knows>
             <foaf:Person>
               <foaf:mbox rdf:resource="..."/>
             </foaf:Person>
          </foaf:knows>
       </foaf:Person>
    </rdf:li>
 </rdf:Seq>
 

Typed node elements means that we write out type information in the short form of

 <foaf:Person rdf:about="...">
     ...
  </foaf:Person>
 

instead of

 <rdf:Description rdf:about="...">
    <rdf:type rdf:resource="http://xmlns.com/foaf/0.1/Person"/>
     ...
  </rdf:Description>
 

Empty property elements are of the form

 <foaf:Person>
    <foaf:homepage rdf:resource="http://www.cs.vu.nl/˜marta"/>
 </foaf:Person>
 

instead of

 <foaf:Person>
    <foaf:homepage>
       <rdf:Description rdf:about="http://www.cs.vu.nl/˜marta"/>
    <foaf:homepage>
 </foaf:Person>
 

Author:

Peter Mika (pmika@cs.vu.nl), Michael Grove

Nested Class Summary

Nested classes/interfaces inherited from class com.stardog.stark.io.rdfxml.RDFXMLWriter

RDFXMLWriter.RDFXMLWriterFactory

Field Summary

Fields inherited from class com.stardog.stark.io.rdfxml.RDFXMLWriter

defaultNamespace, headerWritten, lastWrittenSubject, mOptions, mWriter, namespaceTable, writingStarted

Constructor Summary

Constructors

Constructor	Description
RDFXMLPrettyWriter(java.io.OutputStream theStream, Options theOptions)

Method Summary

Modifier and Type	Method	Description
void	close()
void	flush()
protected void	flushPendingStatements()
void	handle(Statement theStmt)	Write the given Statement
protected void	writeHeader()
protected void	writeIndents(int n)	Writes n indents.
protected void	writeStartTag(java.lang.String namespace, java.lang.String localName)

Methods inherited from class com.stardog.stark.io.rdfxml.RDFXMLWriter

comment, end, format, getValidNodeId, namespace, setNamespace, start, writeAttribute, writeAttribute, writeCharacterData, writeEndOfEmptyTag, writeEndOfStartTag, writeEndTag, writeIndent, writeNewLine, writeStartOfStartTag

Methods inherited from class java.lang.Object

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

Constructor Detail

RDFXMLPrettyWriter

public RDFXMLPrettyWriter(java.io.OutputStream theStream,
                          Options theOptions)

Method Detail

writeHeader

protected void writeHeader()
                    throws java.io.IOException

Overrides:

writeHeader in class RDFXMLWriter

Throws:

java.io.IOException

flush

public void flush()
           throws java.io.IOException

Specified by:

flush in interface java.io.Flushable

Throws:

java.io.IOException

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException

flushPendingStatements

protected void flushPendingStatements()
                               throws java.io.IOException,
                                      WritingFailed

Overrides:

flushPendingStatements in class RDFXMLWriter

Throws:

java.io.IOException

WritingFailed

handle

public void handle(@Nonnull
                   Statement theStmt)
            throws WritingFailed

Write the given Statement

Specified by:

handle in interface RDFHandler

Specified by:

handle in interface RDFWriter

Overrides:

handle in class RDFXMLWriter

Parameters:

theStmt - the statement to write

Throws:

WritingFailed

writeStartTag

protected void writeStartTag(java.lang.String namespace,
                             java.lang.String localName)
                      throws java.io.IOException

Throws:

java.io.IOException

writeIndents

protected void writeIndents(int n)
                     throws java.io.IOException

Writes n indents.

Throws:

java.io.IOException