private bool TryWritingStartElement(IUriNode node)
{
FriendlyRdfXmlWriter.Split(node.Uri, out string nsUri, out string localName);
if (!XmlSpecsHelper.IsNCName(localName))
{
return(false);
}
this.writer.WriteStartElement(localName, nsUri);
return(true);
}
/// <summary>
/// Compares two Literal Nodes.
/// </summary>
/// <param name="a">First Literal Node.</param>
/// <param name="b">Second Literal Node.</param>
/// <param name="culture">Culture to use for lexical string comparisons where more natural comparisons are not possible/applicable.</param>
/// <param name="comparisonOptions">String Comparison options used for lexical string comparisons where more natural comparisons are not possible/applicable.</param>
/// <returns></returns>
public static int CompareLiterals(ILiteralNode a, ILiteralNode b, CultureInfo culture, CompareOptions comparisonOptions)
{
if (ReferenceEquals(a, b))
{
return(0);
}
if (a == null)
{
if (b == null)
{
return(0);
}
return(-1);
}
else if (b == null)
{
return(1);
}
// initialize required culture and comparison options
if (culture == null)
{
culture = Options.DefaultCulture;
}
if (comparisonOptions == CompareOptions.None)
{
comparisonOptions = Options.DefaultComparisonOptions;
}
// Literal Nodes are ordered based on Type and lexical form
if (a.DataType == null && b.DataType != null)
{
// Untyped Literals are less than Typed Literals
// Return a -1 to indicate this
return(-1);
}
else if (a.DataType != null && b.DataType == null)
{
// Typed Literals are greater than Untyped Literals
// Return a 1 to indicate this
return(1);
}
else if (a.DataType == null && b.DataType == null)
{
return(culture.CompareInfo.Compare(a.Value, b.Value, comparisonOptions));
}
else if (EqualityHelper.AreUrisEqual(a.DataType, b.DataType))
{
// Are we using a known and orderable DataType?
String type = a.DataType.AbsoluteUri;
if (!XmlSpecsHelper.IsSupportedType(type))
{
// Don't know how to order so use specified order on the value
return(culture.CompareInfo.Compare(a.Value, b.Value, comparisonOptions));
}
else
{
try
{
switch (type)
{
case XmlSpecsHelper.XmlSchemaDataTypeBoolean:
// Can use Lexical ordering for this so use specified order on the value
bool aBool, bBool;
if (Boolean.TryParse(a.Value, out aBool))
{
if (Boolean.TryParse(b.Value, out bBool))
{
return(aBool.CompareTo(bBool));
}
else
{
return(-1);
}
}
else
{
if (Boolean.TryParse(b.Value, out bBool))
{
return(1);
}
goto default;
}
case XmlSpecsHelper.XmlSchemaDataTypeByte:
// Remember that xsd:byte is actually equivalent to SByte in .Net
// Extract the Byte Values and compare
sbyte aSByte, bSByte;
if (SByte.TryParse(a.Value, out aSByte))
{
if (SByte.TryParse(b.Value, out bSByte))
{
return(aSByte.CompareTo(bSByte));
}
else
{
return(-1);
}
}
else
{
if (SByte.TryParse(b.Value, out bSByte))
{
return(1);
}
goto default;
}
case XmlSpecsHelper.XmlSchemaDataTypeUnsignedByte:
// Remember that xsd:unsignedByte is equivalent to Byte in .Net
// Extract the Byte Values and compare
byte aByte, bByte;
if (Byte.TryParse(a.Value, out aByte))
{
if (Byte.TryParse(b.Value, out bByte))
{
return(aByte.CompareTo(bByte));
}
else
{
return(-1);
}
}
else
{
if (Byte.TryParse(b.Value, out bByte))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeInt:
case XmlSpecsHelper.XmlSchemaDataTypeInteger:
case XmlSpecsHelper.XmlSchemaDataTypeLong:
case XmlSpecsHelper.XmlSchemaDataTypeShort:
// Extract the Integer Values and compare
long aInt64, bInt64;
if (Int64.TryParse(a.Value, out aInt64))
{
if (Int64.TryParse(b.Value, out bInt64))
{
return(aInt64.CompareTo(bInt64));
}
else
{
return(-1);
}
}
else
{
if (Int64.TryParse(b.Value, out bInt64))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeNegativeInteger:
case XmlSpecsHelper.XmlSchemaDataTypeNonPositiveInteger:
// Extract the Integer Values, ensure negative and compare
long aNegInt, bNegInt;
if (Int64.TryParse(a.Value, out aNegInt))
{
if (Int64.TryParse(b.Value, out bNegInt))
{
if (aNegInt >= 0)
{
if (bNegInt >= 0)
{
goto default;
}
else
{
return(1);
}
}
else if (bNegInt >= 0)
{
return(-1);
}
else
{
return(aNegInt.CompareTo(bNegInt));
}
}
else if (aNegInt >= 0)
{
goto default;
}
else
{
return(-1);
}
}
else
{
if (Int64.TryParse(b.Value, out bNegInt))
{
if (bNegInt >= 0)
{
goto default;
}
else
{
return(1);
}
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeUnsignedInt:
case XmlSpecsHelper.XmlSchemaDataTypeUnsignedLong:
case XmlSpecsHelper.XmlSchemaDataTypeUnsignedShort:
case XmlSpecsHelper.XmlSchemaDataTypeNonNegativeInteger:
case XmlSpecsHelper.XmlSchemaDataTypePositiveInteger:
// Unsigned Integers
// Note that for NonNegativeInteger and PositiveInteger we don't need to do the
// same checking we have to do for their inverse types since parsing into an
// Unsigned Long ensures that they must be positive
ulong aUInt64, bUInt64;
if (UInt64.TryParse(a.Value, out aUInt64))
{
if (UInt64.TryParse(b.Value, out bUInt64))
{
return(aUInt64.CompareTo(bUInt64));
}
else
{
return(-1);
}
}
else
{
if (UInt64.TryParse(b.Value, out bUInt64))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeDouble:
// Extract the Double Values and compare
double aDouble, bDouble;
if (Double.TryParse(a.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out aDouble))
{
if (Double.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bDouble))
{
return(aDouble.CompareTo(bDouble));
}
else
{
return(-1);
}
}
else
{
if (Double.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bDouble))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeDecimal:
// Extract the Decimal Values and compare
decimal aDecimal, bDecimal;
if (decimal.TryParse(a.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out aDecimal))
{
if (decimal.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bDecimal))
{
return(aDecimal.CompareTo(bDecimal));
}
else
{
return(-1);
}
}
else
{
if (decimal.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bDecimal))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeFloat:
// Extract the Float Values and compare
float aFloat, bFloat;
if (Single.TryParse(a.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out aFloat))
{
if (Single.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bFloat))
{
return(aFloat.CompareTo(bFloat));
}
else
{
return(-1);
}
}
else
{
if (Single.TryParse(b.Value, NumberStyles.Any, CultureInfo.InvariantCulture, out bFloat))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeHexBinary:
// Extract the numeric value of the Hex encoded Binary and compare
long aHex, bHex;
if (Int64.TryParse(a.Value, NumberStyles.HexNumber, null, out aHex))
{
if (Int64.TryParse(b.Value, NumberStyles.HexNumber, null, out bHex))
{
return(aHex.CompareTo(bHex));
}
else
{
return(-1);
}
}
else
{
if (Int64.TryParse(b.Value, NumberStyles.HexNumber, null, out bHex))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeBase64Binary:
// Extract the numeric value of the Base 64 encoded Binary and compare
byte[] aBin, bBin;
try
{
aBin = Convert.FromBase64String(a.Value);
try
{
bBin = Convert.FromBase64String(b.Value);
if (aBin.Length > bBin.Length)
{
return(1);
}
else if (aBin.Length < bBin.Length)
{
return(-1);
}
else
{
for (int i = 0; i < aBin.Length; i++)
{
if (aBin[i] != bBin[i])
{
return(aBin[i].CompareTo(bBin[i]));
}
}
return(0);
}
}
catch
{
return(-1);
}
}
catch
{
try
{
bBin = Convert.FromBase64String(b.Value);
return(1);
}
catch
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeString:
// String Type
// Can use Lexical Ordering for thisgoto default;
case XmlSpecsHelper.XmlSchemaDataTypeAnyUri:
// Uri Type
// Try and convert to a URI and use lexical ordering
Uri aUri, bUri;
try
{
aUri = UriFactory.Create(a.Value);
try
{
bUri = UriFactory.Create(b.Value);
return(CompareUris(aUri, bUri));
}
catch
{
return(-1);
}
}
catch
{
try
{
bUri = UriFactory.Create(b.Value);
return(1);
}
catch
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeDate:
case XmlSpecsHelper.XmlSchemaDataTypeDateTime:
// Extract the Date Times and compare
DateTimeOffset aDateTimeOffset, bDateTimeOffset;
if (DateTimeOffset.TryParse(a.Value, out aDateTimeOffset))
{
if (DateTimeOffset.TryParse(b.Value, out bDateTimeOffset))
{
return(aDateTimeOffset.CompareTo(bDateTimeOffset));
}
else
{
return(-1);
}
}
else
{
if (DateTimeOffset.TryParse(b.Value, out bDateTimeOffset))
{
return(1);
}
else
{
goto default;
}
}
case XmlSpecsHelper.XmlSchemaDataTypeDuration:
case XmlSpecsHelper.XmlSchemaDataTypeDayTimeDuration:
// Extract the TimeSpan's and compare
TimeSpan aTimeSpan, bTimeSpan;
try
{
aTimeSpan = XmlConvert.ToTimeSpan(a.Value);
try
{
bTimeSpan = XmlConvert.ToTimeSpan(b.Value);
return(aTimeSpan.CompareTo(bTimeSpan));
}
catch
{
return(-1);
}
}
catch
{
try
{
bTimeSpan = XmlConvert.ToTimeSpan(b.Value);
return(1);
}
catch
{
goto default;
}
}
default:
// Don't know how to order so use lexical ordering on the value
// return String.Compare(a.Value, b.Value, culture, comparisonOptions);
return(culture.CompareInfo.Compare(a.Value, b.Value, comparisonOptions));
}
}
catch
{
// There was some error suggesting a non-valid value for a type
// e.g. "example"^^xsd:integer
// In this case just use lexical ordering on the value
// return String.Compare(a.Value, b.Value, culture, comparisonOptions);
return(culture.CompareInfo.Compare(a.Value, b.Value, comparisonOptions));
}
}
}
else
{
// No way of ordering by value if the Data Types are different
// Order by Data Type Uri
// This is required or the Value ordering between types won't occur correctly
return(CompareUris(a.DataType, b.DataType));
}
}
/// <summary>
/// Is something a valid partial QName?
/// </summary>
/// <param name="value">Value</param>
/// <returns></returns>
protected virtual bool IsValidPartialQName(String value)
{
String ns, localname;
if (value.Contains(':'))
{
ns = value.Substring(0, value.IndexOf(':'));
localname = value.Substring(value.IndexOf(':') + 1);
}
else
{
ns = value;
localname = String.Empty;
}
//Namespace Validation
if (!ns.Equals(String.Empty))
{
//Allowed empty Namespace
if (ns.StartsWith("-"))
{
//Can't start with a -
return(false);
}
else
{
char[] nchars = ns.ToCharArray();
if (XmlSpecsHelper.IsNameStartChar(nchars[0]) && nchars[0] != '_')
{
if (nchars.Length > 1)
{
for (int i = 1; i < nchars.Length; i++)
{
//Not a valid Name Char
if (!XmlSpecsHelper.IsNameChar(nchars[i]))
{
return(false);
}
if (nchars[i] == '.')
{
return(false);
}
}
//If we reach here the Namespace is OK
}
else
{
//Only 1 Character which was valid so OK
}
}
else
{
//Doesn't start with a valid Name Start Char
return(false);
}
}
}
//Local Name Validation
if (!localname.Equals(String.Empty))
{
//Allowed empty Local Name
char[] lchars = localname.ToCharArray();
if (XmlSpecsHelper.IsNameStartChar(lchars[0]))
{
if (lchars.Length > 1)
{
for (int i = 1; i < lchars.Length; i++)
{
//Not a valid Name Char
if (!XmlSpecsHelper.IsNameChar(lchars[i]))
{
return(false);
}
if (lchars[i] == '.')
{
return(false);
}
}
//If we reach here the Local Name is OK
}
else
{
//Only 1 Character which was valid so OK
}
}
else
{
//Not a valid Name Start Char
return(false);
}
}
//If we reach here then it's all valid
return(true);
}
/// <summary>
/// Compares two Nodes
/// </summary>
/// <param name="x">Node</param>
/// <param name="y">Node</param>
/// <returns></returns>
public override int Compare(IValuedNode x, IValuedNode y)
{
// Nulls are less than everything
if (x == null && y == null)
{
return(0);
}
if (x == null)
{
return(-1);
}
if (y == null)
{
return(1);
}
// If the Node Types are different use Node ordering
if (x.NodeType != y.NodeType)
{
return(x.CompareTo(y));
}
if (x.NodeType == NodeType.Literal)
{
try
{
// Do they have supported Data Types?
String xtype, ytype;
try
{
xtype = XmlSpecsHelper.GetSupportedDataType(x);
ytype = XmlSpecsHelper.GetSupportedDataType(y);
}
catch (RdfException)
{
// Can't determine a Data Type for one/both of the Nodes so use Node ordering
return(x.CompareTo(y));
}
if (xtype.Equals(String.Empty) || ytype.Equals(String.Empty))
{
// One/both has an unknown type
if (x.Equals(y))
{
// If RDF Term equality returns true then we return that they are equal
return(0);
}
else
{
// If RDF Term equality returns false then we fall back to Node Ordering
return(x.CompareTo(y));
}
}
else
{
// Both have known types
SparqlNumericType xnumtype = x.NumericType;
SparqlNumericType ynumtype = y.NumericType;
SparqlNumericType numtype = (SparqlNumericType)Math.Max((int)xnumtype, (int)ynumtype);
if (numtype != SparqlNumericType.NaN)
{
if (xnumtype == SparqlNumericType.NaN)
{
return(1);
}
else if (ynumtype == SparqlNumericType.NaN)
{
return(-1);
}
// Both are Numeric so use Numeric ordering
try
{
return(this.NumericCompare(x, y, numtype));
}
catch (FormatException)
{
if (x.Equals(y))
{
return(0);
}
// Otherwise fall back to Node Ordering
return(x.CompareTo(y));
}
catch (RdfQueryException)
{
// If this errors try RDF Term equality since that might still give equality
if (x.Equals(y))
{
return(0);
}
// Otherwise fall back to Node Ordering
return(x.CompareTo(y));
}
}
else if (xtype.Equals(ytype))
{
switch (xtype)
{
case XmlSpecsHelper.XmlSchemaDataTypeDate:
return(DateCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeDateTime:
return(DateTimeCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeString:
// Both Strings so use Lexical string ordering
return(((ILiteralNode)x).Value.CompareTo(((ILiteralNode)y).Value));
default:
// Use node ordering
return(x.CompareTo(y));
}
}
else
{
String commontype = XmlSpecsHelper.GetCompatibleSupportedDataType(xtype, ytype, true);
if (commontype.Equals(String.Empty))
{
// Use Node ordering
return(x.CompareTo(y));
}
else
{
switch (commontype)
{
case XmlSpecsHelper.XmlSchemaDataTypeDate:
return(DateCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeDateTime:
return(DateTimeCompare(x, y));
default:
// Use Node ordering
return(x.CompareTo(y));
}
}
}
}
}
catch
{
// If error then can't determine ordering so fall back to node ordering
return(x.CompareTo(y));
}
}
else
{
// If not Literals use Node ordering
return(x.CompareTo(y));
}
}
/// <summary>
/// Compares two Nodes
/// </summary>
/// <param name="x">Node</param>
/// <param name="y">Node</param>
/// <returns></returns>
public virtual int Compare(INode x, INode y)
{
// Nulls are less than everything
if (x == null && y == null)
{
return(0);
}
if (x == null)
{
return(-1);
}
if (y == null)
{
return(1);
}
// If the Node Types are different use Node ordering
if (x.NodeType != y.NodeType)
{
return(x.CompareTo(y));
}
if (x.NodeType == NodeType.Literal)
{
// Do they have supported Data Types?
String xtype, ytype;
try
{
xtype = XmlSpecsHelper.GetSupportedDataType(x);
ytype = XmlSpecsHelper.GetSupportedDataType(y);
}
catch (RdfException)
{
// Can't determine a Data Type for one/both of the Nodes so use Node ordering
return(x.CompareTo(y));
}
if (xtype.Equals(String.Empty) || ytype.Equals(String.Empty))
{
// One/both has an unknown type
if (x.Equals(y))
{
// If RDF Term equality returns true then we return that they are equal
return(0);
}
else
{
// If RDF Term equality returns false then we error
// UNLESS they have the same Datatype
throw new RdfQueryException("Unable to determine ordering since one/both arguments has an Unknown Type");
}
}
else
{
// Both have known types
SparqlNumericType xnumtype = SparqlSpecsHelper.GetNumericTypeFromDataTypeUri(xtype);
SparqlNumericType ynumtype = SparqlSpecsHelper.GetNumericTypeFromDataTypeUri(ytype);
SparqlNumericType numtype = (SparqlNumericType)Math.Max((int)xnumtype, (int)ynumtype);
if (numtype != SparqlNumericType.NaN)
{
if (xnumtype == SparqlNumericType.NaN || ynumtype == SparqlNumericType.NaN)
{
// If one is non-numeric then we can't assume non-equality
throw new RdfQueryException("Unable to determine ordering since one/both arguments does not return a Number");
}
// Both are Numeric so use Numeric ordering
try
{
return(this.NumericCompare(x, y, numtype));
}
catch (FormatException)
{
if (x.Equals(y))
{
return(0);
}
throw new RdfQueryException("Unable to determine ordering since one/both arguments does not contain a valid value for it's type");
}
catch (RdfQueryException)
{
// If this errors try RDF Term equality since
if (x.Equals(y))
{
return(0);
}
throw new RdfQueryException("Unable to determine ordering since one/both arguments was not a valid numeric");
}
}
else if (xtype.Equals(ytype))
{
switch (xtype)
{
case XmlSpecsHelper.XmlSchemaDataTypeDate:
return(DateCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeDateTime:
return(DateTimeCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeString:
// Both Strings so use Lexical string ordering
#if NETCORE
return(Options.DefaultCulture.CompareInfo.Compare(((ILiteralNode)x).Value,
((ILiteralNode)y).Value, Options.DefaultComparisonOptions));
#else
return(String.Compare(((ILiteralNode)x).Value, ((ILiteralNode)y).Value, Options.DefaultCulture, Options.DefaultComparisonOptions));
#endif
default:
// Use node ordering
return(x.CompareTo(y));
}
}
else
{
String commontype = XmlSpecsHelper.GetCompatibleSupportedDataType(xtype, ytype, true);
if (commontype.Equals(String.Empty))
{
// Use Node ordering
return(x.CompareTo(y));
}
else
{
switch (commontype)
{
case XmlSpecsHelper.XmlSchemaDataTypeDate:
return(DateCompare(x, y));
case XmlSpecsHelper.XmlSchemaDataTypeDateTime:
return(DateTimeCompare(x, y));
default:
// Use Node ordering
return(x.CompareTo(y));
}
}
}
}
}
else
{
// If not Literals use Node ordering
return(x.CompareTo(y));
}
}
