Prototype for RDBMS projection functionality

Contains 2 options, one finished, the other half finished for review/eval by Mika.

persistence/runtime/src/main/java/org/eclipsefoundation/persistence/dao/impl/BaseHibernateDao.java

@@ -47,7 +47,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
 
     @Override
     public <T extends BareNode> List<T> get(RDBMSQuery<T> q) {
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             throw new MaintenanceException();
         }
         // handle root request parameters (setting headers to track limit and max count)
@@ -58,8 +58,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
             LOGGER.debug("Querying DB using the following query: {}", q.getFilter().getSelectSql());
         }
         // build base query
-        TypedQuery<T> query = getEntityManager().createQuery(q.getFilter().getSelectSql(),
-                q.getDocType());
+        TypedQuery<T> query = getEntityManager().createQuery(q.getFilter().getSelectSql(), q.getDocType());
 
         // add ordinal parameters
         int ord = 1;
@@ -80,7 +79,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
     @Transactional
     @Override
     public <T extends BareNode> List<T> add(RDBMSQuery<T> q, List<T> documents) {
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             throw new MaintenanceException();
         }
         if (LOGGER.isDebugEnabled()) {
@@ -113,7 +112,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
     @Transactional
     @Override
     public <T extends BareNode> void delete(RDBMSQuery<T> q) {
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             throw new MaintenanceException();
         }
 
@@ -132,7 +131,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
     @Transactional
     @Override
     public Long count(RDBMSQuery<?> q) {
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             throw new MaintenanceException();
         }
         if (LOGGER.isDebugEnabled()) {
@@ -154,16 +153,15 @@ public abstract class BaseHibernateDao implements PersistenceDao {
 
     @Override
     public <T extends BareNode> T getReference(Object id, Class<T> type) {
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             throw new MaintenanceException();
         }
         return getEntityManager().getReference(type, id);
     }
 
     /**
-     * Handles operations that should happen on a "root" or main DB request for a
-     * fulfilled request. This is done to ensure that values such as DB max are
-     * abided.
+     * Handles operations that should happen on a "root" or main DB request for a fulfilled request. This is done to
+     * ensure that values such as DB max are abided.
      */
     private void handleRoot(RDBMSQuery<?> q) {
         // check if count has been performed, if not do so and set it to the response
@@ -192,7 +190,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
     @Override
     public HealthCheckResponse call() {
         HealthCheckResponseBuilder b = HealthCheckResponse.named("DB readiness");
-        if (maintenanceFlag) {
+        if (isMaintenanceMode()) {
             return b.down().withData("error", "Maintenance flag is set").build();
         }
         return b.up().build();
@@ -205,7 +203,13 @@ public abstract class BaseHibernateDao implements PersistenceDao {
      * @param persistenceUnit the persistence unit targeted for the transaction
      * @return entity manager object linked to current transaction
      */
-    protected EntityManager getEntityManager() {
+    @Override
+    public EntityManager getEntityManager() {
         return inner;
     }
+
+    @Override
+    public boolean isMaintenanceMode() {
+        return maintenanceFlag;
+    }
 }