class EasyRdf_Serialiser_Turtle in Zircon Profile 8.0
Same name and namespace in other branches
- 8 vendor/easyrdf/easyrdf/lib/EasyRdf/Serialiser/Turtle.php \EasyRdf_Serialiser_Turtle
Class to serialise an EasyRdf_Graph to Turtle with no external dependancies.
@package EasyRdf @copyright Copyright (c) 2009-2013 Nicholas J Humfrey @license http://www.opensource.org/licenses/bsd-license.php
Hierarchy
- class \EasyRdf_Serialiser
- class \EasyRdf_Serialiser_Turtle
Expanded class hierarchy of EasyRdf_Serialiser_Turtle
1 string reference to 'EasyRdf_Serialiser_Turtle'
- Format.php in vendor/
easyrdf/ easyrdf/ lib/ EasyRdf/ Format.php
File
- vendor/
easyrdf/ easyrdf/ lib/ EasyRdf/ Serialiser/ Turtle.php, line 48
View source
class EasyRdf_Serialiser_Turtle extends EasyRdf_Serialiser {
private $outputtedBnodes = array();
/**
* Given a IRI string, escape and enclose in angle brackets.
*
* @param string $resourceIri
* @return string
*/
public static function escapeIri($resourceIri) {
$escapedIri = str_replace('>', '\\>', $resourceIri);
return "<{$escapedIri}>";
}
/**
* Given a string, enclose in quotes and escape any quotes in the string.
* Strings containing tabs, linefeeds or carriage returns will be
* enclosed in three double quotes (""").
*
* @param string $value
* @return string
*/
public static function quotedString($value) {
if (preg_match('/[\\t\\n\\r]/', $value)) {
$escaped = str_replace(array(
'\\',
'"""',
), array(
'\\\\',
'\\"""',
), $value);
return '"""' . $escaped . '"""';
}
else {
$escaped = str_replace(array(
'\\',
'"',
), array(
'\\\\',
'\\"',
), $value);
return '"' . $escaped . '"';
}
}
/**
* Given a an EasyRdf_Resource or URI, convert it into a string, suitable to
* be written to a Turtle document. URIs will be shortened into CURIES
* where possible.
*
* @param EasyRdf_Resource $resource The resource to convert to a Turtle string
* @param boolean $createNamespace If true, a new namespace may be created
* @return string
*/
public function serialiseResource($resource, $createNamespace = false) {
if (is_object($resource)) {
if ($resource
->isBNode()) {
return $resource
->getUri();
}
$resource = $resource
->getUri();
}
$short = EasyRdf_Namespace::shorten($resource, $createNamespace);
if ($short) {
$this
->addPrefix($short);
return $short;
}
return self::escapeIri($resource);
}
/**
* Given an EasyRdf_Literal object, convert it into a string, suitable to
* be written to a Turtle document. Supports multiline literals and literals with
* datatypes or languages.
*
* @param EasyRdf_Literal $literal
* @return string
*/
public function serialiseLiteral($literal) {
$value = strval($literal);
$quoted = self::quotedString($value);
if ($datatype = $literal
->getDatatypeUri()) {
if ($datatype == 'http://www.w3.org/2001/XMLSchema#integer') {
return sprintf('%d', $value);
}
elseif ($datatype == 'http://www.w3.org/2001/XMLSchema#decimal') {
return sprintf('%s', $value);
}
elseif ($datatype == 'http://www.w3.org/2001/XMLSchema#double') {
return sprintf('%e', $value);
}
elseif ($datatype == 'http://www.w3.org/2001/XMLSchema#boolean') {
return sprintf('%s', $value);
}
else {
$escaped = $this
->serialiseResource($datatype, true);
return sprintf('%s^^%s', $quoted, $escaped);
}
}
elseif ($lang = $literal
->getLang()) {
return $quoted . '@' . $lang;
}
else {
return $quoted;
}
}
/**
* Convert an EasyRdf object into a string suitable to
* be written to a Turtle document.
*
* @param EasyRdf_Resource|EasyRdf_Literal $object
* @return string
*/
public function serialiseObject($object) {
if ($object instanceof EasyRdf_Resource) {
return $this
->serialiseResource($object);
}
elseif ($object instanceof EasyRdf_Literal) {
return $this
->serialiseLiteral($object);
}
else {
throw new InvalidArgumentException("serialiseObject() requires \$object to be " . "of type EasyRdf_Resource or EasyRdf_Literal");
}
}
/**
* Protected method to serialise a RDF collection
* @ignore
*/
protected function serialiseCollection($node, $indent) {
$turtle = '(';
$count = 0;
while ($node) {
if ($id = $node
->getBNodeId()) {
$this->outputtedBnodes[$id] = true;
}
$value = $node
->get('rdf:first');
$node = $node
->get('rdf:rest');
if ($node and $node
->hasProperty('rdf:first')) {
$count++;
}
if ($value !== null) {
$serialised = $this
->serialiseObject($value);
if ($count) {
$turtle .= "\n{$indent} {$serialised}";
}
else {
$turtle .= " " . $serialised;
}
}
}
if ($count) {
$turtle .= "\n{$indent})";
}
else {
$turtle .= " )";
}
return $turtle;
}
/**
* Protected method to serialise the properties of a resource
* @ignore
*/
protected function serialiseProperties($res, $depth = 1) {
$properties = $res
->propertyUris();
$indent = str_repeat(' ', $depth * 2 - 1);
$turtle = '';
if (count($properties) > 1) {
$turtle .= "\n{$indent}";
}
$pCount = 0;
foreach ($properties as $property) {
if ($property === 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type') {
$pStr = 'a';
}
else {
$pStr = $this
->serialiseResource($property, true);
}
if ($pCount) {
$turtle .= " ;\n{$indent}";
}
$turtle .= ' ' . $pStr;
$oCount = 0;
foreach ($res
->all("<{$property}>") as $object) {
if ($oCount) {
$turtle .= ',';
}
if ($object instanceof EasyRdf_Collection) {
$turtle .= ' ' . $this
->serialiseCollection($object, $indent);
}
elseif ($object instanceof EasyRdf_Resource and $object
->isBNode()) {
$id = $object
->getBNodeId();
$rpcount = $this
->reversePropertyCount($object);
if ($rpcount <= 1 and !isset($this->outputtedBnodes[$id])) {
// Nested unlabelled Blank Node
$this->outputtedBnodes[$id] = true;
$turtle .= ' [';
$turtle .= $this
->serialiseProperties($object, $depth + 1);
$turtle .= ' ]';
}
else {
// Multiple properties pointing to this blank node
$turtle .= ' ' . $this
->serialiseObject($object);
}
}
else {
$turtle .= ' ' . $this
->serialiseObject($object);
}
$oCount++;
}
$pCount++;
}
if ($depth == 1) {
$turtle .= " .";
if ($pCount > 1) {
$turtle .= "\n";
}
}
elseif ($pCount > 1) {
$turtle .= "\n" . str_repeat(' ', ($depth - 1) * 2 - 1);
}
return $turtle;
}
/**
* @ignore
*/
protected function serialisePrefixes() {
$turtle = '';
foreach ($this->prefixes as $prefix => $count) {
$url = EasyRdf_Namespace::get($prefix);
$turtle .= "@prefix {$prefix}: <{$url}> .\n";
}
return $turtle;
}
/**
* @ignore
*/
protected function serialiseSubjects(EasyRdf_Graph $graph, $filterType) {
$turtle = '';
foreach ($graph
->resources() as $resource) {
/** @var $resource EasyRdf_Resource */
// If the resource has no properties - don't serialise it
$properties = $resource
->propertyUris();
if (count($properties) == 0) {
continue;
}
// Is this node of the right type?
$thisType = $resource
->isBNode() ? 'bnode' : 'uri';
if ($thisType != $filterType) {
continue;
}
if ($thisType == 'bnode') {
$id = $resource
->getBNodeId();
if (isset($this->outputtedBnodes[$id])) {
// Already been serialised
continue;
}
$this->outputtedBnodes[$id] = true;
$rpcount = $this
->reversePropertyCount($resource);
if ($rpcount == 0) {
$turtle .= '[]';
}
else {
$turtle .= $this
->serialiseResource($resource);
}
}
else {
$turtle .= $this
->serialiseResource($resource);
}
$turtle .= $this
->serialiseProperties($resource);
$turtle .= "\n";
}
return $turtle;
}
/**
* Serialise an EasyRdf_Graph to Turtle.
*
* @param EasyRdf_Graph $graph An EasyRdf_Graph object.
* @param string $format The name of the format to convert to.
* @param array $options
* @throws EasyRdf_Exception
* @return string The RDF in the new desired format.
*/
public function serialise($graph, $format, array $options = array()) {
parent::checkSerialiseParams($graph, $format);
if ($format != 'turtle' and $format != 'n3') {
throw new EasyRdf_Exception("EasyRdf_Serialiser_Turtle does not support: {$format}");
}
$this->prefixes = array();
$this->outputtedBnodes = array();
$turtle = '';
$turtle .= $this
->serialiseSubjects($graph, 'uri');
$turtle .= $this
->serialiseSubjects($graph, 'bnode');
if (count($this->prefixes)) {
return $this
->serialisePrefixes() . "\n" . $turtle;
}
else {
return $turtle;
}
}
}Members
Name |
Modifiers | Type | Description | Overrides |
|---|---|---|---|---|
|
EasyRdf_Serialiser:: |
protected | property | ||
|
EasyRdf_Serialiser:: |
protected | function | Keep track of the prefixes used while serialising @ignore | |
|
EasyRdf_Serialiser:: |
protected | function | Check and cleanup parameters passed to serialise() method @ignore | |
|
EasyRdf_Serialiser:: |
protected | function | Protected method to get the number of reverse properties for a resource If a resource only has a single property, the number of values for that property is returned instead. @ignore | |
|
EasyRdf_Serialiser:: |
public | function | 4 | |
|
EasyRdf_Serialiser_Turtle:: |
private | property | ||
|
EasyRdf_Serialiser_Turtle:: |
public static | function | Given a IRI string, escape and enclose in angle brackets. | |
|
EasyRdf_Serialiser_Turtle:: |
public static | function | Given a string, enclose in quotes and escape any quotes in the string. Strings containing tabs, linefeeds or carriage returns will be enclosed in three double quotes ("""). | |
|
EasyRdf_Serialiser_Turtle:: |
public | function |
Serialise an EasyRdf_Graph to Turtle. Overrides EasyRdf_Serialiser:: |
|
|
EasyRdf_Serialiser_Turtle:: |
protected | function | Protected method to serialise a RDF collection @ignore | |
|
EasyRdf_Serialiser_Turtle:: |
public | function | Given an EasyRdf_Literal object, convert it into a string, suitable to be written to a Turtle document. Supports multiline literals and literals with datatypes or languages. | |
|
EasyRdf_Serialiser_Turtle:: |
public | function | Convert an EasyRdf object into a string suitable to be written to a Turtle document. | |
|
EasyRdf_Serialiser_Turtle:: |
protected | function | @ignore | |
|
EasyRdf_Serialiser_Turtle:: |
protected | function | Protected method to serialise the properties of a resource @ignore | |
|
EasyRdf_Serialiser_Turtle:: |
public | function | Given a an EasyRdf_Resource or URI, convert it into a string, suitable to be written to a Turtle document. URIs will be shortened into CURIES where possible. | |
|
EasyRdf_Serialiser_Turtle:: |
protected | function | @ignore |