Merge pull request #200 from kbss-cvut/issue#31-add-new-function-to-c…

…ompute-time-diff

[New] Add new function to compute difference between two xsd:dateTime events

s-pipes-core/src/main/java/cz/cvut/spipes/function/time/Duration.java

@@ -0,0 +1,41 @@
+package cz.cvut.spipes.function.time;
+
+import cz.cvut.spipes.constants.KBSS_TIMEF;
+import cz.cvut.spipes.function.ValueFunction;
+import org.apache.jena.datatypes.xsd.XSDDatatype;
+import org.apache.jena.graph.Node;
+import org.apache.jena.graph.NodeFactory;
+import org.apache.jena.sparql.expr.NodeValue;
+import org.apache.jena.sparql.function.FunctionEnv;
+import org.topbraid.spin.arq.AbstractFunction2;
+
+import javax.xml.bind.DatatypeConverter;
+import java.util.Calendar;
+
+/**
+ * Computes the time difference between two xsd:dateTime values in milliseconds and returns the result as xsd:long.
+ * Returns a negative value if the first parameter represents a later time.
+ */
+public class Duration extends AbstractFunction2 implements ValueFunction {
+
+    private static final String TYPE_IRI = KBSS_TIMEF.getURI() + "duration-in-ms";
+
+    @Override
+    public String getTypeURI() {
+        return TYPE_IRI;
+    }
+
+    @Override
+    protected NodeValue exec(Node startDateTime, Node endDateTime, FunctionEnv functionEnv) {
+        Calendar start = parseNodeToCalendar(startDateTime);
+        Calendar end = parseNodeToCalendar(endDateTime);
+
+        long duration = end.getTimeInMillis()-start.getTimeInMillis();
+        Node node = NodeFactory.createLiteralByValue(duration, XSDDatatype.XSDlong);
+        return NodeValue.makeNode(node);
+    }
+
+    private Calendar parseNodeToCalendar(Node dateTime){
+        return DatatypeConverter.parseDateTime(dateTime.getLiteral().getLexicalForm());
+    }
+}

s-pipes-core/src/test/java/cz/cvut/spipes/function/time/DurationTest.java

@@ -0,0 +1,60 @@
+package cz.cvut.spipes.function.time;
+
+import org.apache.jena.datatypes.RDFDatatype;
+import org.apache.jena.datatypes.xsd.XSDDatatype;
+import org.apache.jena.graph.Node;
+import org.apache.jena.sparql.expr.NodeValue;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class DurationTest {
+
+    @Test
+    public void execSimple() {
+
+        Duration duration = new Duration();
+        Node startDateTime = getDateTimeNode("2023-08-21T13:00:00.100").asNode();
+        Node endDateTime = getDateTimeNode("2023-08-21T13:00:00.250").asNode();
+
+        NodeValue durationInMS = duration.exec(startDateTime, endDateTime, null);
+        long expected = 150;
+        assertEquals(expected,durationInMS.getInteger().intValue());
+    }
+
+    @Test
+    public void execStartDateTimeIsLaterThenEndDateTime() {
+
+        Duration duration = new Duration();
+        Node startDateTime = getDateTimeNode("2023-08-21T13:20:00").asNode();
+        Node endDateTime = getDateTimeNode("2023-08-21T13:00:00").asNode();
+
+        NodeValue durationInMS = duration.exec(startDateTime, endDateTime,null);
+        long expected = -1200000;
+        assertEquals(expected,durationInMS.getInteger().intValue());
+    }
+
+    @Test
+    public void execTimeZoneFormat() {
+
+        Duration duration = new Duration();
+        Node startDateTime = getDateTimeNode("2023-08-21T15:30:00.100-05:00").asNode();
+        Node endDateTime = getDateTimeNode("2023-08-21T14:30:05.600-06:00").asNode();
+
+        NodeValue durationInMS = duration.exec(startDateTime, endDateTime,null);
+        long expected = 5500;
+        assertEquals(expected,durationInMS.getInteger().intValue());
+    }
+
+    private NodeValue getDateTimeNode(String dateTime){
+        return getNode(dateTime, XSDDatatype.XSDdateTime);
+    }
+
+    private NodeValue getNode(String time, RDFDatatype datatype) {
+        return NodeValue.makeNode(
+                time,
+                null,
+                datatype.getURI()
+        );
+    }
+}