Add the EntityManagerConnection factory.

src/main/java/space/kklochko/jpa_hospital_example/db/factories/EntityManagerConnection.java

@@ -0,0 +1,24 @@
+package space.kklochko.jpa_hospital_example.db.factories;
+
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.EntityManagerFactory;
+import jakarta.persistence.Persistence;
+import lombok.Data;
+
+@Data
+public class EntityManagerConnection  {
+    private String unitName;
+
+    public EntityManagerConnection(String unitName) {
+        setUnitName(unitName);
+    }
+
+    public EntityManagerConnection() {
+        setUnitName("jpa_hospital_example");
+    }
+
+    public EntityManager connect() {
+        EntityManagerFactory factory = Persistence.createEntityManagerFactory(getUnitName());
+        return factory.createEntityManager();
+    }
+}