us.daveread.basicquery.util

Class RdbToRdf

java.lang.Object

us.daveread.basicquery.util.RdbToRdf

All Implemented Interfaces:

java.lang.Runnable

public class RdbToRdf
extends java.lang.Object
implements java.lang.Runnable

Export a SQL ResultSet to triples

Author:

David Read

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Map<java.lang.String,java.lang.String>	datatypeProperties Collection of datatype properties already encountered
private static java.lang.String	DEFAULT_DATA_CLASS Default class for all the exported records
private static java.lang.String	DEFAULT_NAMESPACE Default namespace for the data loaded from the RDB
private static java.text.SimpleDateFormat	FORMAT_DATE Used for formatting DB date column values into the ontology
private static java.text.SimpleDateFormat	FORMAT_DATE_TIME Used for formatting DB timestamp (date and time) column values into the ontology
private static java.text.SimpleDateFormat	FORMAT_TIME Used for formatting DB time column values into the ontology
private static java.lang.String[]	FORMATS The set of formats that can be output.
private long	latestNumberOfRowsExported Count of DB rows exported as of last execution of this instance
private static org.apache.log4j.Logger	LOGGER Logging instance
private com.hp.hpl.jena.ontology.OntModel	ontModel The loaded ontology
private java.lang.String	outputFileName The name (and path if necessary) to the output file for the output triples
private java.lang.String	outputFormat The output format for the triples This will default to match the input format TODO allow control from command line or configuration
private java.lang.String	query The query returning the result set
private java.lang.String	rdfDataClass The class of the data instances generated
private java.lang.String	rdfNamespace The namespace to use for the generated resources and predicates
private static java.lang.String	REASONING_LEVEL The reasoning level to use TODO allow this to be controlled from command line or configuration
protected static java.lang.String[]	REASONING_LEVELS The reasoning levels available.
private java.sql.ResultSet	resultSet The result set to be exported
private java.sql.ResultSetMetaData	resultSetMetaData The metadata associated with the result set
private static int	UNKNOWN Constant used if a value cannot be found in an array

Constructor Summary

Constructors

Constructor and Description
RdbToRdf(java.lang.String pOutputFileName, java.lang.String pQuery, java.sql.ResultSet pResultSet) Constructor - sets up the input and output file paths and the triples map

Method Summary

Methods

Modifier and Type	Method and Description
private void	addInstance(java.lang.String subject, java.lang.String namespace, java.lang.String className) Add the PK value as a new instance of the data class.
private void	addStatement(java.lang.String subject, java.lang.String predicate, java.lang.String objectLiteral, int rdbColumnType, java.lang.String namespace, java.lang.String className) Add the RDB data, treating the column data as a literal value
private java.lang.String	convertToCamelCase(java.lang.String name, boolean initialUpper) Convert a string into CamelCase or camelCase
private java.lang.String	convertToClassName(java.lang.String name) Convert a string to a CamelCase format matching class naming convention
private java.lang.String	convertToInstanceName(java.lang.String name) Convert a string into a camelCase format matching instance naming convention
private java.lang.String	convertToPropertyName(java.lang.String name) Convert a string into a camelCase format matching property naming convention
private com.hp.hpl.jena.ontology.OntModel	createModel(java.lang.String reasoningLevel) Create a model with a reasoner set based on the chosen reasoning level.
static java.lang.String	getArrayAsCSV(java.lang.String[] array) Create a CSV list from a String array
static java.lang.String	getFormatsAsCSV() Get the set of defined ontology file formats that the program can load as a CSV list String
static int	getIndexValue(java.lang.String[] array, java.lang.String name) Find a String value within and array of Strings.
long	getLatestNumberOfRowsExported() Get the number of DB rows exported to triples as of the last exeuction of this instance
java.lang.String	getOutputFileName() Get the output file name for the location of the generated report
private java.lang.String	getQuery() Get the query returning the result set
static int	getReasoningLevelIndex(java.lang.String reasonerName) Get the index position of the supplied reasoning level label
private java.sql.ResultSet	getResultSet() Get the result set to be exported
private java.sql.ResultSetMetaData	getResultSetMetaData() Get the metadata for the result set to be exported
private void	loadModel(java.lang.String reasoningLevel) Obtain an ontology model set to the chosen reasoning level.
private void	loadModelFromRdb() Setup the ontology model from the data anbd metadata in the result set
private void	makeDatatypeProperty(java.lang.String namespace, java.lang.String propertyName) Check to see if this property URI has been asserted as an owl:DatatypeProperty.
private static java.lang.String	makeSafeURIValue(java.lang.String value) Very crude method to create a value that will work as an RDF resource - e.g.
void	run() Perform the steps to load, compare and report on the ontology
void	setOutputFileName(java.lang.String pOutputFileName) Set the output file name, where the report should be written
private void	setQuery(java.lang.String pQuery) Set the query returning the result set
private void	setResultSet(java.sql.ResultSet pResultSet) Set the result set to be exported
private void	setResultSetMetaData(java.sql.ResultSetMetaData pResultSetMetaData) Set the metadata for the result set to be exported
private void	storeModel() Writes the triples to a data file.

Methods inherited from class java.lang.Object

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

Field Detail

LOGGER

private static final org.apache.log4j.Logger LOGGER

Logging instance

DEFAULT_NAMESPACE

private static final java.lang.String DEFAULT_NAMESPACE

Default namespace for the data loaded from the RDB

See Also:

Constant Field Values

DEFAULT_DATA_CLASS

private static final java.lang.String DEFAULT_DATA_CLASS

Default class for all the exported records

See Also:

Constant Field Values

FORMAT_DATE

private static final java.text.SimpleDateFormat FORMAT_DATE

Used for formatting DB date column values into the ontology

FORMAT_TIME

private static final java.text.SimpleDateFormat FORMAT_TIME

Used for formatting DB time column values into the ontology

FORMAT_DATE_TIME

private static final java.text.SimpleDateFormat FORMAT_DATE_TIME

Used for formatting DB timestamp (date and time) column values into the ontology

rdfNamespace

private java.lang.String rdfNamespace

The namespace to use for the generated resources and predicates

rdfDataClass

private java.lang.String rdfDataClass

The class of the data instances generated

FORMATS

private static final java.lang.String[] FORMATS

The set of formats that can be output. These are defined by Jena

REASONING_LEVEL

private static final java.lang.String REASONING_LEVEL

The reasoning level to use TODO allow this to be controlled from command line or configuration

See Also:

Constant Field Values

outputFormat

private java.lang.String outputFormat

The output format for the triples This will default to match the input format TODO allow control from command line or configuration

REASONING_LEVELS

protected static final java.lang.String[] REASONING_LEVELS

The reasoning levels available.

UNKNOWN

private static final int UNKNOWN

Constant used if a value cannot be found in an array

See Also:

Constant Field Values

outputFileName

private java.lang.String outputFileName

The name (and path if necessary) to the output file for the output triples

ontModel

private com.hp.hpl.jena.ontology.OntModel ontModel

The loaded ontology

query

private java.lang.String query

The query returning the result set

resultSet

private java.sql.ResultSet resultSet

The result set to be exported

resultSetMetaData

private java.sql.ResultSetMetaData resultSetMetaData

The metadata associated with the result set

datatypeProperties

private java.util.Map<java.lang.String,java.lang.String> datatypeProperties

Collection of datatype properties already encountered

latestNumberOfRowsExported

private long latestNumberOfRowsExported

Count of DB rows exported as of last execution of this instance

Constructor Detail

RdbToRdf

public RdbToRdf(java.lang.String pOutputFileName,
        java.lang.String pQuery,
        java.sql.ResultSet pResultSet)

Constructor - sets up the input and output file paths and the triples map

Parameters:

pOutputFileName - The name (and optional path) for the output

pQuery - The query associated with the result set

pResultSet - The database result set to export

Method Detail

run

public void run()

Perform the steps to load, compare and report on the ontology

Specified by:

run in interface java.lang.Runnable

loadModelFromRdb

private void loadModelFromRdb()

Setup the ontology model from the data anbd metadata in the result set

addInstance

private void addInstance(java.lang.String subject,
               java.lang.String namespace,
               java.lang.String className)

Add the PK value as a new instance of the data class. The name is prepended with the DEFAULT_INSTANCE_NAME_PREFIX to prevent issues with values that start with a digit. This method also adds an RDF label containing the actual value

Parameters:

subject - The subject which will be a class instance

namespace - The namespace for the exported data

className - The class name for the individuals representing the rows of data

addStatement

private void addStatement(java.lang.String subject,
                java.lang.String predicate,
                java.lang.String objectLiteral,
                int rdbColumnType,
                java.lang.String namespace,
                java.lang.String className)

Add the RDB data, treating the column data as a literal value

Parameters:

subject - The subject of the triple

predicate - The predicate of the triple

objectLiteral - The object of the triple (treated as a literal)

rdbColumnType - The SQL data type of the column containing this literal value

namespace - The namespace for the exported data

className - The class name for the individuals representing the rows of data

makeDatatypeProperty

private void makeDatatypeProperty(java.lang.String namespace,
                        java.lang.String propertyName)

Check to see if this property URI has been asserted as an owl:DatatypeProperty. If not, assert it.

Parameters:

namespace - The namespace of the property

propertyName - The name of the property

makeSafeURIValue

private static java.lang.String makeSafeURIValue(java.lang.String value)

Very crude method to create a value that will work as an RDF resource - e.g. removes spaces. If the data contains other special characters then this function will need to be fleshed out.

Parameters:

value - the value to be made URI-safe

Returns:

a URI-safe value (no spaces)

storeModel

private void storeModel()

Writes the triples to a data file.

getFormatsAsCSV

public static final java.lang.String getFormatsAsCSV()

Get the set of defined ontology file formats that the program can load as a CSV list String

Returns:

The known ontology file formats as a CSV list

getArrayAsCSV

public static final java.lang.String getArrayAsCSV(java.lang.String[] array)

Create a CSV list from a String array

Parameters:

array - An array

Returns:

The array values in a CSV list

setOutputFileName

public void setOutputFileName(java.lang.String pOutputFileName)

Set the output file name, where the report should be written

Parameters:

pOutputFileName - The output file name

getOutputFileName

public java.lang.String getOutputFileName()

Get the output file name for the location of the generated report

Returns:

The output file name

setQuery

private void setQuery(java.lang.String pQuery)

Set the query returning the result set

Parameters:

pQuery - The SQL query

getQuery

private java.lang.String getQuery()

Get the query returning the result set

Returns:

The SQL Query

setResultSet

private void setResultSet(java.sql.ResultSet pResultSet)

Set the result set to be exported

Parameters:

pResultSet - The result set

getResultSet

private java.sql.ResultSet getResultSet()

Get the result set to be exported

Returns:

The result set

setResultSetMetaData

private void setResultSetMetaData(java.sql.ResultSetMetaData pResultSetMetaData)

Set the metadata for the result set to be exported

Parameters:

pResultSetMetaData - The metadata

getResultSetMetaData

private java.sql.ResultSetMetaData getResultSetMetaData()

Get the metadata for the result set to be exported

Returns:

The metadata

createModel

private com.hp.hpl.jena.ontology.OntModel createModel(java.lang.String reasoningLevel)

Create a model with a reasoner set based on the chosen reasoning level.

Parameters:

reasoningLevel - The reasoning level for this model

Returns:

The created ontology model

loadModel

private void loadModel(java.lang.String reasoningLevel)

Obtain an ontology model set to the chosen reasoning level. Load the ontology file into the model

Parameters:

reasoningLevel - The selected reasoning level

getReasoningLevelIndex

public static final int getReasoningLevelIndex(java.lang.String reasonerName)

Get the index position of the supplied reasoning level label

Parameters:

reasonerName - A reasoning level label

Returns:

The index position of the reasoning level. Will be equal to the constant UNKNOWN if the value cannot be found in the collection of known reasoning levels

getLatestNumberOfRowsExported

public long getLatestNumberOfRowsExported()

Get the number of DB rows exported to triples as of the last exeuction of this instance

Returns:

The number of DB rows exported

getIndexValue

public static final int getIndexValue(java.lang.String[] array,
                java.lang.String name)

Find a String value within and array of Strings. Return the index position where the value was found.

Parameters:

array - An array of string to search

name - The value to find in the array

Returns:

The position where the value was found in the array. Will be equal to the constant UNKNOWN if the value cannot be found in the collection of known reasoning levels

convertToClassName

private java.lang.String convertToClassName(java.lang.String name)

Convert a string to a CamelCase format matching class naming convention

Parameters:

name - The text to munge into a class name

Returns:

The munged class name

convertToPropertyName

private java.lang.String convertToPropertyName(java.lang.String name)

Convert a string into a camelCase format matching property naming convention

Parameters:

name - The text to munge into a property name

Returns:

The munged property name

convertToInstanceName

private java.lang.String convertToInstanceName(java.lang.String name)

Convert a string into a camelCase format matching instance naming convention

Parameters:

name - The text to munge into an instance (individual) name

Returns:

The munged instance name

convertToCamelCase

private java.lang.String convertToCamelCase(java.lang.String name,
                                  boolean initialUpper)

Convert a string into CamelCase or camelCase

Parameters:

name - The string to convert to camel case

initialUpper - Whether the resulting string should begin with an uppercase character

Returns:

The camel case string