diff --git a/src/main/java/NTNU/IDATT1002/repository/GenericRepository.java b/src/main/java/NTNU/IDATT1002/repository/GenericRepository.java
new file mode 100644
index 0000000000000000000000000000000000000000..5e474d2a15dc7c3735e5665105d5dbd0b663ff97
--- /dev/null
+++ b/src/main/java/NTNU/IDATT1002/repository/GenericRepository.java
@@ -0,0 +1,139 @@
+package NTNU.IDATT1002.repository;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+import java.util.Optional;
+
+
+/**
+ * Generic Entity Repository Abstract Class.
+ * Implements regular Create, Read, Update and Delete operations defined in {@link Repository}.
+ *
+ * This class can be easily extended to support type specific operations through concrete implementations.
+ * @param <T> type of entity
+ * @param <ID> type of entity id
+ * @author Eirik Steira
+ * @version 1.0 19.03.20
+ */
+abstract class GenericRepository<T, ID> implements Repository<T, ID> {
+
+ /**
+ * The type of class which implementations of this class is to operate on.
+ */
+ private Class<T> classType;
+
+ @PersistenceContext
+ protected EntityManager entityManager;
+
+ /**
+ * Constructor to inject {@link EntityManager} dependency.
+ *
+ * @param entityManager the entity manager to utilize
+ */
+ public GenericRepository(EntityManager entityManager) {
+ this.entityManager = entityManager;
+ }
+
+ /**
+ * Set the type of class which this class is to operate on.
+ *
+ * @param classTypeToSet the type of class
+ */
+ public void setClassType(Class<T> classTypeToSet) {
+ classType = classTypeToSet;
+ }
+
+ /**
+ * Saves a given entity and returns the saved instance.
+ *
+ * @param entity not null
+ * @return the saved entity
+ */
+ public Optional<T> save(T entity) {
+ try {
+ persist(entity);
+ return Optional.of(entity);
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+
+ return Optional.empty();
+ }
+
+ /**
+ * Persists the given image album.
+ *
+ * @param entity the image album to persist
+ */
+ private void persist(T entity) {
+ entityManager.getTransaction().begin();
+ entityManager.persist(entity);
+ entityManager.getTransaction().commit();
+ }
+
+ /**
+ * Retrieves all instances of the class type.
+ *
+ * @return all entities
+ */
+ public List<?> findAll() {
+ return entityManager.createQuery("from " + classType.getName())
+ .getResultList();
+ }
+
+ /**
+ * Retrieves an entity with the given id.
+ *
+ * @param id not null
+ * @return the entity with the given id if found, else Optional.empty()
+ */
+ public Optional<T> findById(ID id) {
+ T entity = entityManager.find(classType, id);
+ return entity != null ? Optional.of(entity) : Optional.empty();
+ }
+
+ /**
+ * Deletes an entity with the given id.
+ *
+ * @param id not null
+ */
+ public void deleteById(ID id) {
+ Optional<T> entity = findById(id);
+ entity.ifPresent(this::delete);
+ }
+
+ /**
+ * Deletes the given entity.
+ *
+ * @param entity not null
+ */
+ public void delete(T entity) {
+ try {
+ remove(entity);
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+
+ /**
+ * Removes the given image album.
+ *
+ * @param entity the image album to remove
+ */
+ private void remove(T entity) {
+ entityManager.getTransaction().begin();
+ entityManager.remove(entity);
+ entityManager.getTransaction().commit();
+ }
+
+ /**
+ * Return the number of entities.
+ *
+ * @return the number of entities.
+ */
+ public long count() {
+ return findAll().size();
+ }
+
+}
diff --git a/src/main/java/NTNU/IDATT1002/repository/ImageAlbumRepository.java b/src/main/java/NTNU/IDATT1002/repository/ImageAlbumRepository.java
index 110b722bd67d90fec77195c51ab82b21cb30f659..fa5706cfbbd29ff2f151e4b1817a7e3409b30545 100644
--- a/src/main/java/NTNU/IDATT1002/repository/ImageAlbumRepository.java
+++ b/src/main/java/NTNU/IDATT1002/repository/ImageAlbumRepository.java
@@ -4,81 +4,30 @@ import NTNU.IDATT1002.models.ImageAlbum;
import javax.persistence.EntityManager;
import java.util.List;
-import java.util.Optional;
/**
* Image Album Repository.
*
- * Implements {@link Repository} which supports regular Create, Read, Update and Delete operations.
+ * Implementation of {@link GenericRepository} which supports regular Create, Read, Update and Delete operations.
* @author Eirik Steira
* @version 1.0 19.03.20
- * @see NTNU.IDATT1002.repository.Repository
+ * @see NTNU.IDATT1002.repository.GenericRepository
*/
-public class ImageAlbumRepository implements Repository<ImageAlbum, Long> {
+public class ImageAlbumRepository extends GenericRepository<ImageAlbum, Long> {
/**
* Mapping to @NamedQuery 'find all image albums by title' defined in {@link ImageAlbum}
*/
public static final String IMAGE_ALBUM_FIND_BY_TITLE = "ImageAlbum.findAllByTitle";
- private EntityManager entityManager;
-
/**
- * Constructor to inject {@link EntityManager} dependency.
+ * Constructor to inject {@link EntityManager} dependency and sets the class type to {@link ImageAlbum}
*
- * @param entityManager the entity manager to utilize.
+ * @param entityManager the entity manager to utilize
*/
public ImageAlbumRepository(EntityManager entityManager) {
- this.entityManager = entityManager;
- }
-
- /**
- * Saves a given image album and returns the saved instance.
- *
- * @param imageAlbum the image album to save
- * @return the saved image album
- */
- public Optional<ImageAlbum> save(ImageAlbum imageAlbum) {
- try {
- persist(imageAlbum);
- return Optional.of(imageAlbum);
- } catch (Exception e) {
- e.printStackTrace();
- }
-
- return Optional.empty();
- }
-
- /**
- * Persists the given image album.
- *
- * @param imageAlbum the image album to persist
- */
- private void persist(ImageAlbum imageAlbum) {
- entityManager.getTransaction().begin();
- entityManager.persist(imageAlbum);
- entityManager.getTransaction().commit();
- }
-
- /**
- * Retrieves all instances of type image album.
- *
- * @return all saved image albums
- */
- public List<?> findAll() {
- return entityManager.createQuery("from ImageAlbum ").getResultList();
- }
-
-
- /**
- * Retrieves an image album with the given id.
- *
- * @param id the if of the image album to find
- * @return the entity with the given id if found, else Optional.empty()
- */
- public Optional<ImageAlbum> findById(Long id) {
- ImageAlbum imageAlbum = entityManager.find(ImageAlbum.class, id);
- return imageAlbum != null ? Optional.of(imageAlbum) : Optional.empty();
+ super(entityManager);
+ setClassType(ImageAlbum.class);
}
/**
@@ -93,57 +42,4 @@ public class ImageAlbumRepository implements Repository<ImageAlbum, Long> {
.getResultList();
}
- /**
- * Deletes an image album with the given id.
- *
- * @param id the id of the image album to delete
- */
- public void deleteById(Long id) {
- Optional<ImageAlbum> imageAlbum = findById(id);
- imageAlbum.ifPresent(this::delete);
- }
-
- /**
- * Deletes the given image album.
- *
- * @param imageAlbum the image album to delete
- */
- public void delete(ImageAlbum imageAlbum) {
- try {
- remove(imageAlbum);
- } catch (Exception e) {
- e.printStackTrace();
- }
- }
-
- /**
- * Removes the given image album.
- *
- * @param imageAlbum the image album to remove
- */
- private void remove(ImageAlbum imageAlbum) {
- entityManager.getTransaction().begin();
- entityManager.remove(imageAlbum);
- entityManager.getTransaction().commit();
- }
-
- /**
- * Return the number of image albums.
- *
- * @return the number of image albums
- */
- public long count() {
- return findAll().size();
- }
-
- /**
- * Return whether the given image album exists.
- *
- * @param imageAlbum image album to check existence for
- * @return true if the image album exist, else false
- */
- public boolean exists(ImageAlbum imageAlbum) {
- return findById(imageAlbum.getId())
- .isPresent();
- }
}
diff --git a/src/main/java/NTNU/IDATT1002/repository/Repository.java b/src/main/java/NTNU/IDATT1002/repository/Repository.java
index 28c9ecf5d2cb77e08c8ef1e2e54993b6b3d70819..bbd732fc3bc47cfcf7caf1e4dd8f4cb0516bb596 100644
--- a/src/main/java/NTNU/IDATT1002/repository/Repository.java
+++ b/src/main/java/NTNU/IDATT1002/repository/Repository.java
@@ -58,11 +58,4 @@ public interface Repository<T, ID> {
*/
long count();
- /**
- * Return whether the given entity exists.
- *
- * @param entity not null
- * @return true if the entity exist, else false
- */
- boolean exists(T entity);
}
diff --git a/src/test/java/NTNU/IDATT1002/repository/ImageAlbumRepositoryTest.java b/src/test/java/NTNU/IDATT1002/repository/ImageAlbumRepositoryTest.java
index 2369dc84791ed543b5133ddfac2f2b129d8403d7..f8ba07fbf0d0fe425270a3008b2a147931a4e57e 100644
--- a/src/test/java/NTNU/IDATT1002/repository/ImageAlbumRepositoryTest.java
+++ b/src/test/java/NTNU/IDATT1002/repository/ImageAlbumRepositoryTest.java
@@ -158,27 +158,4 @@ class ImageAlbumRepositoryTest {
assertEquals(2, imageAlbumCount);
}
- /**
- * Test that checking for existence returns true when the given entity exists.
- */
- @Test
- void testExistsReturnsTrueWhenEntityExists() {
- Optional<ImageAlbum> savedImageAlbum = imageAlbumRepository.save(new ImageAlbum());
- boolean imageAlbumExists = imageAlbumRepository.exists(savedImageAlbum.get());
-
- assertTrue(imageAlbumExists);
- }
-
- /**
- * Test that checking for existence returns false when the given entity does not exist.
- */
- @Test
- void testExistsReturnsFalseWhenEntityDoesNotExist() {
- ImageAlbum notSavedImageAlbum = new ImageAlbum();
- notSavedImageAlbum.setId(IMAGE_ALBUM_INITIAL_ID);
-
- boolean imageAlbumExists = imageAlbumRepository.exists(notSavedImageAlbum);
-
- assertFalse(imageAlbumExists);
- }
}
\ No newline at end of file