Handle Instant literals in TemporalAccessorLiteral (#5506)

Author: hmottestad

core/model-api/src/main/java/org/eclipse/rdf4j/model/base/AbstractLiteral.java

@@ -32,6 +32,9 @@
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.time.DateTimeException;
+import java.time.Instant;
+import java.time.OffsetDateTime;
+import java.time.ZoneOffset;
 import java.time.format.DateTimeFormatter;
 import java.time.format.DateTimeFormatterBuilder;
 import java.time.format.DateTimeParseException;
@@ -704,15 +707,24 @@ private static int key(Predicate<ChronoField> include, ChronoField... fields) {
 
 			this.value = value;
 
-			datatype = DATATYPES.get(key(value));
+			TemporalAccessor lexicalValue = value;
 
-			if (datatype == null) {
+			CoreDatatype.XSD detectedDatatype = DATATYPES.get(key(lexicalValue));
+
+			if (detectedDatatype == null && value.isSupported(ChronoField.INSTANT_SECONDS)) {
+				Instant instant = Instant.from(value);
+				lexicalValue = OffsetDateTime.ofInstant(instant, ZoneOffset.UTC);
+				detectedDatatype = DATATYPES.get(key(lexicalValue));
+			}
+
+			if (detectedDatatype == null) {
 				throw new IllegalArgumentException(String.format(
 						"value <%s> cannot be represented by an XML Schema date/time datatype", value
 				));
 			}
 
-			this.label = FORMATTERS.get(datatype).format(value);
+			datatype = detectedDatatype;
+			this.label = FORMATTERS.get(datatype).format(lexicalValue);
 		}
 
 		@Override

core/model/src/test/java/org/eclipse/rdf4j/model/util/LiteralsTest.java

@@ -11,13 +11,15 @@
 package org.eclipse.rdf4j.model.util;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.fail;
 
+import java.time.Instant;
 import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.IllformedLocaleException;
@@ -107,6 +109,17 @@ public void testNormaliseBCP47Tag() {
 				.isThrownBy(() -> Literals.normalizeLanguageTag("ru-ua-latn"));
 	}
 
+	@Test
+	public void valuesLiteralSupportsInstant() {
+		Instant instant = Instant.parse("2022-08-01T21:14:38.470534100Z");
+
+		Literal literal = Values.literal(instant);
+
+		assertThat(Instant.parse(literal.getLabel())).isEqualTo(instant);
+		assertThat(literal.getDatatype()).isEqualTo(XSD.DATETIME);
+		assertThat(literal.temporalAccessorValue()).isEqualTo(instant);
+	}
+
 	/**
 	 * Test method for
 	 * {@link org.eclipse.rdf4j.model.util.Literals#getLabel(org.eclipse.rdf4j.model.Literal, java.lang.String)} .