MODLD-998: Create TitleLabelGenerator

NEWS.md

@@ -3,6 +3,7 @@
 - Concept label generation now orders labels as FOCUS first, followed by sorted SUB_FOCUS entries [MODLD-913](https://folio-org.atlassian.net/browse/MODLD-913)
 - Update Predicate Dictionary: add IS_TRANSLATION_OF, RELATED_WORK, ADAPTED_AS_MOTION_PICTURE, SEQUEL, SEQUEL_TO and remove RELATED_TO [MODLD-1002](https://folio-org.atlassian.net/browse/MODLD-1002)
 - Fix the relation URLs to match the URLs defined in https://bibfra.me/vocab/relation [MODLD-1011](https://folio-org.atlassian.net/browse/MODLD-1011)
+- Create TitleLabelGenerator [MODLD-998](https://folio-org.atlassian.net/browse/MODLD-998)
 
 ## v1.9.9 (13-02-2026)
 - Update Mapping for 300$b & $e (Physical description & Accompanying material) [MODLD-508](https://folio-org.atlassian.net/browse/MODLD-508)

src/main/java/org/folio/ld/dictionary/label/LabelGeneratorService.java

@@ -3,6 +3,7 @@
 import java.util.List;
 import org.folio.ld.dictionary.label.generators.ConceptLabelGenerator;
 import org.folio.ld.dictionary.label.generators.HubLabelGenerator;
+import org.folio.ld.dictionary.label.generators.TitleLabelGenerator;
 import org.folio.ld.dictionary.model.Resource;
 
 public class LabelGeneratorService {
@@ -12,7 +13,8 @@ public class LabelGeneratorService {
   public LabelGeneratorService() {
     this.generators = List.of(
       new ConceptLabelGenerator(),
-      new HubLabelGenerator()
+      new HubLabelGenerator(),
+      new TitleLabelGenerator()
     );
   }
 

src/main/java/org/folio/ld/dictionary/label/LabelHelper.java

@@ -0,0 +1,17 @@
+package org.folio.ld.dictionary.label;
+
+import java.util.Optional;
+import lombok.experimental.UtilityClass;
+import org.folio.ld.dictionary.model.Resource;
+import tools.jackson.databind.JsonNode;
+
+@UtilityClass
+public class LabelHelper {
+  public static Optional<String> getPropertyValue(Resource resource, String property) {
+    return Optional.of(resource)
+      .map(Resource::getDoc)
+      .map(doc -> doc.get(property))
+      .map(node -> node.get(0))
+      .map(JsonNode::asString);
+  }
+}

src/main/java/org/folio/ld/dictionary/label/generators/HubLabelGenerator.java

@@ -6,6 +6,7 @@
 import static org.folio.ld.dictionary.PredicateDictionary.TITLE;
 import static org.folio.ld.dictionary.PropertyDictionary.TERM;
 import static org.folio.ld.dictionary.ResourceTypeDictionary.HUB;
+import static org.folio.ld.dictionary.label.LabelHelper.getPropertyValue;
 
 import java.util.Optional;
 import java.util.stream.Stream;
@@ -15,7 +16,6 @@
 import org.folio.ld.dictionary.label.LabelGenerator;
 import org.folio.ld.dictionary.model.Resource;
 import org.folio.ld.dictionary.model.ResourceEdge;
-import tools.jackson.databind.JsonNode;
 
 public class HubLabelGenerator implements LabelGenerator {
   @Override
@@ -52,12 +52,4 @@ private Stream<Resource> getOutgoingEdges(Resource resource, PredicateDictionary
       .filter(re -> re.getPredicate().equals(predicate))
       .map(ResourceEdge::getTarget);
   }
-
-  private Optional<String> getPropertyValue(Resource resource, String property) {
-    return Optional.of(resource)
-      .map(Resource::getDoc)
-      .map(doc -> doc.get(property))
-      .map(node -> node.get(0))
-      .map(JsonNode::asString);
-  }
 }

src/main/java/org/folio/ld/dictionary/label/generators/TitleLabelGenerator.java

@@ -0,0 +1,40 @@
+package org.folio.ld.dictionary.label.generators;
+
+import static java.util.stream.Collectors.joining;
+import static org.folio.ld.dictionary.PropertyDictionary.MAIN_TITLE;
+import static org.folio.ld.dictionary.PropertyDictionary.PART_NAME;
+import static org.folio.ld.dictionary.PropertyDictionary.PART_NUMBER;
+import static org.folio.ld.dictionary.PropertyDictionary.SUBTITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.ABBREVIATED_TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.PARALLEL_TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.VARIANT_TITLE;
+import static org.folio.ld.dictionary.label.LabelHelper.getPropertyValue;
+
+import java.util.Optional;
+import java.util.stream.Stream;
+import org.folio.ld.dictionary.label.LabelGenerator;
+import org.folio.ld.dictionary.model.Resource;
+
+public class TitleLabelGenerator implements LabelGenerator {
+  @Override
+  public boolean supports(Resource resource) {
+    return resource.isOfType(TITLE)
+      || resource.isOfType(VARIANT_TITLE)
+      || resource.isOfType(PARALLEL_TITLE)
+      || resource.isOfType(ABBREVIATED_TITLE);
+  }
+
+  @Override
+  public String getLabel(Resource resource) {
+    var mainTitle = getPropertyValue(resource, MAIN_TITLE.getValue());
+    var subtitle = getPropertyValue(resource, SUBTITLE.getValue());
+    var partNumber = getPropertyValue(resource, PART_NUMBER.getValue());
+    var partName = getPropertyValue(resource, PART_NAME.getValue());
+
+    return Stream.of(mainTitle, subtitle, partNumber, partName)
+      .filter(Optional::isPresent)
+      .map(Optional::get)
+      .collect(joining(" "));
+  }
+}

src/test/java/org/folio/ld/dictionary/label/TitleLabelGeneratorTest.java

@@ -0,0 +1,60 @@
+package org.folio.ld.dictionary.label;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.ABBREVIATED_TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.PARALLEL_TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.TITLE;
+import static org.folio.ld.dictionary.ResourceTypeDictionary.VARIANT_TITLE;
+
+import java.util.stream.Stream;
+import lombok.SneakyThrows;
+import org.folio.ld.dictionary.ResourceTypeDictionary;
+import org.folio.ld.dictionary.model.Resource;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import tools.jackson.databind.json.JsonMapper;
+
+class TitleLabelGeneratorTest {
+  private final JsonMapper mapper = new JsonMapper();
+  private final LabelGeneratorService generator = new LabelGeneratorService();
+
+  @ParameterizedTest
+  @MethodSource("supportedTitleTypes")
+  @SneakyThrows
+  void getLabel_joinsAvailableTitleProperties(ResourceTypeDictionary type) {
+    var title = new Resource()
+      .setId(1L)
+      .addType(type)
+      .setDoc(mapper.readTree("""
+        {
+          "http://bibfra.me/vocab/library/mainTitle": ["Main"],
+          "http://bibfra.me/vocab/library/subTitle": ["Subtitle"],
+          "http://bibfra.me/vocab/library/partNumber": ["Part 1"],
+          "http://bibfra.me/vocab/library/partName": ["Part Name"]
+        }
+        """));
+
+    assertThat(generator.getLabel(title)).isEqualTo("Main Subtitle Part 1 Part Name");
+  }
+
+  @Test
+  @SneakyThrows
+  void getLabel_skipsMissingProperties() {
+    var title = new Resource()
+      .setId(1L)
+      .addType(TITLE)
+      .setDoc(mapper.readTree("""
+        {
+          "http://bibfra.me/vocab/library/mainTitle": ["Main"],
+          "http://bibfra.me/vocab/library/partName": ["Part Name"]
+        }
+        """));
+
+    assertThat(generator.getLabel(title)).isEqualTo("Main Part Name");
+  }
+
+  private static Stream<ResourceTypeDictionary> supportedTitleTypes() {
+    return Stream.of(TITLE, VARIANT_TITLE, PARALLEL_TITLE, ABBREVIATED_TITLE);
+  }
+}