/**
* Create a new query.
*
* Query language is any language supported by rasqal, including "rdql",
* "sparql" and "triples".
*
* The syntax of the query is not checked until it is executed.
*
* @param string $query_string The contents of the query
* @param string $base_uri The base URI to use
* @param string $query_language The language of the query (default rdql)
* @param string $query_uri The URI of the query language or NULL
* @return void
* @throws LibRDF_Error If unable to create a new query
* @access public
*/
public function __construct($query_string, $base_uri = NULL, $query_language = "rdql", $query_uri = NULL)
{
if ($base_uri) {
$base_uri = new LibRDF_URI($base_uri);
}
if ($query_uri) {
$query_uri = new LibRDF_URI($query_uri);
}
$this->query = librdf_new_query(librdf_php_get_world(), $query_language, $query_uri ? $query_uri->getURI() : $query_uri, $query_string, $base_uri ? $base_uri->getURI() : $base_uri);
if (!$this->query) {
throw new LibRDF_Error("Unable to create a new query");
}
}
/**
* Set a prefix to URI mapping.
*
* @param string $uri The namespace URI
* @param string $prefix The string prefix to use
* @return void
* @throws LibRDF_Error If unable to set the prefix
* @access public
*/
public function setNamespace($uri, $prefix)
{
$uri = new LibRDF_URI($uri);
$ret = librdf_serializer_set_namespace($this->serializer, $uri->getURI(), $prefix);
if ($ret) {
throw new LibRDF_Error("Unable to set namespace prefix");
}
}
/**
* Create a new URINode from a URI object.
*
* @param mixed $uri The URI string or librdf_node value to use
* @return void
* @throws LibRDF_Error If unable to create a new URI
* @access public
*/
public function __construct($uri)
{
if (is_string($uri)) {
$uri = new LibRDF_URI($uri);
$this->node = librdf_new_node_from_uri(librdf_php_get_world(), $uri->getURI());
} elseif (is_resource($uri) and librdf_node_is_resource($uri)) {
$this->node = $uri;
} else {
throw new LibRDF_Error("Argument is not a string or \n librdf_node resource");
}
if (!$this->node) {
throw new LibRDF_Error("Unable to create new URI node");
}
}
/**
* Serialize the model and write the contents to a file.
*
* @param LibRDF_Serializer $serializer The serializer to use
* @param string $file_name The name of the file to which to write
* @param string $base_uri The base URI to use
* @return void
* @throws LibRDF_Error If unable to serialize the model
* @access public
*/
public function serializeStatementsToFile(LibRDF_Serializer $serializer, $file_name, $base_uri = NULL)
{
if ($base_uri) {
$base_uri = new LibRDF_URI($base_uri);
}
$ret = librdf_serializer_serialize_model_to_file($serializer->getSerializer(), $file_name, $base_uri ? $base_uri->getURI() : $base_uri, $this->model);
if ($ret) {
throw new LibRDF_Error("Error serializing model to file");
}
}
/**
* Serialize the results to a string.
*
* @param string $uri The uri of the target syntax or NULL
* @param string $base_uri The base URI for the output or NULL
* @return string The results as a string
* @throws LibRDF_Error If unable to create a string from the results
* @access public
*/
public function to_string($uri = NULL, $base_uri = NULL)
{
if ($uri) {
$uri = new LibRDF_URI($uri);
}
if ($base_uri) {
$base_uri = new LibRDF_URI($base_uri);
}
$ret = librdf_query_results_to_string($this->query_results, $uri ? $uri->getURI() : NULL, $base_uri ? $base_uri->getURI() : NULL);
if ($ret) {
return $ret;
} else {
throw new LibRDF_Error("Unable to convert the query results to a string");
}
}
/**
* Parse a URI and return an iterable object over the statements.
*
* The object returned can be used in PHP foreach statements. It is not
* rewindable.
*
* @param string $uri The URI to parse
* @param string $base_uri The value to use for the base URI if different from $uri
* @return LibRDF_StreamIterator An iterator over the LibRDF_Statements parsed from $uri
* @throws LibRDF_Error If unable to parse the URI
* @access public
*/
public function parseURI($uri, $base_uri = NULL)
{
$uri = new LibRDF_URI($uri);
if ($base_uri) {
$base_uri = new LibRDF_URI($base_uri);
}
$stream = librdf_parser_parse_as_stream($this->parser, $uri->getURI(), $base_uri ? $base_uri->getURI() : $base_uri);
if (!$stream) {
throw new LibRDF_Error("Unable to parse URI");
}
return new LibRDF_StreamIterator($stream, $this);
}
/**
* Compare this URI against another URI for equality.
*
* @param LibRDF_URI $uri The URI against which to compare
* @return boolean Whether the two URIs are equal
* @access public
*/
public function isEqual(LibRDF_URI $uri)
{
if (librdf_uri_equals($this->uri, $uri->getURI())) {
return true;
} else {
return false;
}
}
