Merge branch 'generic-entity-dao' into 'milestone-1'

Superclasses for entity and DAO

See merge request !1

src/main/java/dao/EntityDao.java

+package dao;
+
+import entity.GenericEntity;
+
+import java.util.List;
+
+/**
+ * @author Daniel Puchala
+ */
+public interface EntityDao<Entity extends GenericEntity> {
+
+    void create(Entity entity);
+
+    void delete(Entity entity);
+
+    List<Entity> findAll();
+
+    Entity findById(Long id);
+}

src/main/java/dao/EntityDaoImpl.java

+package dao;
+
+import entity.GenericEntity;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Root;
+import java.util.List;
+
+/**
+ * @author Daniel Puchala
+ */
+public abstract class EntityDaoImpl<Entity extends GenericEntity> implements EntityDao<Entity> {
+
+    @PersistenceContext
+    protected EntityManager em;
+
+    protected final Class<Entity> entityClass;
+
+    public EntityDaoImpl(Class<Entity> entityClass) {
+        this.entityClass = entityClass;
+    }
+
+    public void create(Entity entity) {
+        em.persist(entity);
+    }
+
+    public void delete(Entity entity) {
+        em.remove(entity);
+    }
+
+    public List<Entity> findAll() {
+        CriteriaBuilder cb = em.getCriteriaBuilder();
+        CriteriaQuery<Entity> query = cb.createQuery(entityClass);
+
+        Root<Entity> entity = query.from(entityClass);
+        query.select(entity);
+
+        return em.createQuery(query).getResultList();
+    }
+
+    public Entity findById(Long id) {
+        return em.find(entityClass, id);
+    }
+}

src/main/java/dao/ExampleDao.java

-package dao;
-
-public interface ExampleDao {
-}

src/main/java/entity/ExampleEntity.java

-package entity;
-
-public interface ExampleEntity {
-}

src/main/java/entity/GenericEntity.java

+package entity;
+
+import jakarta.validation.constraints.NotNull;
+
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.Temporal;
+import javax.persistence.TemporalType;
+import java.time.LocalTime;
+
+/**
+ * @author Daniel Puchala
+ */
+public class GenericEntity {
+
+    @Id
+    @GeneratedValue(strategy= GenerationType.IDENTITY)
+    private Long id;
+
+    @NotNull
+    @Temporal(TemporalType.DATE)
+    private LocalTime createdAt;
+
+    @NotNull
+    @Temporal(TemporalType.DATE)
+    private LocalTime updatedAt;
+}