Add multi-hop TL

Author: dfuchss

framework/common/src/main/java/edu/kit/kastel/mcse/ardoco/core/api/tracelink/MultiHopTransitiveTraceLink.java

@@ -0,0 +1,89 @@
+package edu.kit.kastel.mcse.ardoco.core.api.tracelink;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import edu.kit.kastel.mcse.ardoco.core.api.entity.Entity;
+
+public final class MultiHopTransitiveTraceLink<A extends Entity, B extends Entity> extends TraceLink<A, B> {
+
+    private static final long serialVersionUID = 850583103292008395L;
+
+    private static final Logger logger = LoggerFactory.getLogger(MultiHopTransitiveTraceLink.class);
+
+    private final TraceLink<A, ?> firstTraceLink;
+    private final TraceLink<?, B> lastTraceLink;
+
+    private final List<? extends TraceLink<?, ?>> allLinks;
+
+    private MultiHopTransitiveTraceLink(TraceLink<A, ?> firstTraceLink, TraceLink<?, B> lastTraceLink, List<? extends TraceLink<?, ?>> allLinks) {
+        super(firstTraceLink.getFirstEndpoint(), lastTraceLink.getSecondEndpoint());
+        this.firstTraceLink = firstTraceLink;
+        this.lastTraceLink = lastTraceLink;
+        this.allLinks = allLinks;
+    }
+
+    public static <A extends Entity, B extends Entity> Optional<MultiHopTransitiveTraceLink<A, B>> createTransitiveTraceLink(TraceLink<A, ?> firstTraceLink,
+            TraceLink<?, B> lastTraceLink, List<? extends TraceLink<?, ?>> intermediateLinks) {
+
+        if (intermediateLinks == null || intermediateLinks.isEmpty()) {
+            throw new IllegalArgumentException("Please use " + TransitiveTraceLink.class.getSimpleName());
+        }
+
+        Objects.requireNonNull(firstTraceLink);
+        Objects.requireNonNull(lastTraceLink);
+
+        List<TraceLink<?, ?>> completeList = new ArrayList<>();
+        completeList.add(firstTraceLink);
+        completeList.addAll(intermediateLinks);
+        completeList.add(lastTraceLink);
+
+        for (int i = 1; i < completeList.size(); i++) {
+            if (!TransitiveTraceLink.isValidTransitiveTraceLink(completeList.get(i - 1), completeList.get(i))) {
+                MultiHopTransitiveTraceLink.logger.debug("Invalid transition: {} -> {}", completeList.get(i - 1), completeList.get(i));
+                return Optional.empty();
+            }
+        }
+
+        return Optional.of(new MultiHopTransitiveTraceLink<>(firstTraceLink, lastTraceLink, completeList));
+    }
+
+    public TraceLink<A, ?> getFirstTraceLink() {
+        return this.firstTraceLink;
+    }
+
+    public TraceLink<?, B> getLastTraceLink() {
+        return this.lastTraceLink;
+    }
+
+    public List<? extends TraceLink<?, ?>> getAllLinks() {
+        return new ArrayList<TraceLink<?, ?>>(this.allLinks);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(this.allLinks);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (!(obj instanceof MultiHopTransitiveTraceLink<?, ?> other)) {
+            return false;
+        }
+        return Objects.equals(this.allLinks, other.allLinks);
+    }
+
+    @Override
+    public String toString() {
+        return this.asPair().toString();
+    }
+
+}