Add code to handle a possible uninitialized object

Author: pjewald

src/main/java/com/parallax/server/blocklyprop/services/impl/UserServiceImpl.java

@@ -54,12 +54,25 @@ public void setConfiguration(Configuration configuration) {
 
     @Override
     public User getUser(Long idUser) {
-        return userDao.getUser(idUser).into(User.class);
+        if (userDao != null) {
+            return userDao.getUser(idUser).into(User.class);
+        }
+        else {
+            LOG.error("UserDAO is not initialized before first use!");
+            return null;
+        }
+        
     }
 
     @Override
     public List<UserRecord> getAllUsers() {
-        return userDao.getAll();
+        if (userDao != null) {
+            return userDao.getAll();
+        }
+        else {
+            LOG.error("UserDAO is not initialized before first use!");
+            return null;
+        }
     }
 
     @Override
@@ -68,7 +81,12 @@ public String getUserScreenName(Long idUser) {
         String name = "";
 
         try {
-            name = userDao.getUser(idUser).getScreenname();
+            if (userDao != null) {
+                name = userDao.getUser(idUser).getScreenname();
+            }
+            else {
+                LOG.error("UserDAO is not initialized before first use!");
+            }
         }
         catch (NullPointerException ex) {
             LOG.error("Error retreiving name for userID: {}", idUser);