Merge pull request #185 from kit-data-manager/fix-48-entities-must-not-be-root

fix: RootDataEntity identifier is not allowed for other entities.

Author: Pfeil

src/main/java/edu/kit/datamanager/ro_crate/entities/AbstractEntity.java

@@ -8,6 +8,7 @@
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 
+import edu.kit.datamanager.ro_crate.entities.data.RootDataEntity;
 import edu.kit.datamanager.ro_crate.entities.serializers.ObjectNodeSerializer;
 import edu.kit.datamanager.ro_crate.entities.validation.EntityValidation;
 import edu.kit.datamanager.ro_crate.entities.validation.JsonSchemaValidation;
@@ -363,7 +364,7 @@ protected String getId() {
          * @return the generic builder.
          */
         public T setId(String id) {
-            if (id != null) {
+            if (id != null && !id.equals(RootDataEntity.ID)) {
                 if (IdentifierUtils.isValidUri(id)) {
                     this.id = id;
                 } else {

src/main/java/edu/kit/datamanager/ro_crate/entities/data/RootDataEntity.java

@@ -9,7 +9,7 @@
  */
 public class RootDataEntity extends DataSetEntity {
 
-  private static final String ID = "./";
+  public static final String ID = "./";
 
   public RootDataEntity(AbstractDataSetBuilder<?> entityBuilder) {
     super(entityBuilder);

src/test/java/edu/kit/datamanager/ro_crate/entities/data/DataSetEntityTest.java

@@ -2,25 +2,36 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.io.IOException;
 
 import edu.kit.datamanager.ro_crate.HelpFunctions;
 import edu.kit.datamanager.ro_crate.objectmapper.MyObjectMapper;
 import java.net.URI;
 import java.nio.file.Paths;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
+import java.util.Objects;
 
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 /**
  * @author Nikola Tzotchev on 5.2.2022 г.
  * @version 1
  */
 public class DataSetEntityTest {
 
+    @Test
+    void testImpossibleRootId() {
+        DataSetEntity e = new DataSetEntity.DataSetBuilder()
+                .setId("./")
+                .addProperty("not_root", true)
+                .build();
+        assertNotNull(e.getId());
+        assertFalse(e.getId().isBlank());
+        assertNotEquals(RootDataEntity.ID, e.getId());
+    }
+
     @Test
     void testSimpleDirDeserialization() throws IOException {