Hibernate: avoid potential deadlock on c3p0

If StartGameHandler takes the last connection available in the c3p0
pool, then Game.start() will block inside sessionProvider.get().  But
since this is nested within, StartGameHandler never gets to the
`finally` block where it releases its connection.

src/main/java/net/socialgamer/cah/data/Game.java

@@ -703,47 +703,39 @@ public class Game {
    *         game is already started, or doesn't have enough cards, but hopefully callers and
    *         clients would prevent that from happening!
    */
-  public boolean start() {
+  public boolean start(Session session) {
-    Session session = null;
+    if (state != GameState.LOBBY || !hasEnoughCards(session)) {
-    try {
+      return false;
-      session = sessionProvider.get();
-      if (state != GameState.LOBBY || !hasEnoughCards(session)) {
-        return false;
-      }
-      boolean started;
-      final int numPlayers = players.size();
-      if (numPlayers >= 3) {
-        // Pick a random start judge, though the "next" judge will actually go first.
-        judgeIndex = (int) (Math.random() * numPlayers);
-        started = true;
-      } else {
-        started = false;
-      }
-      if (started) {
-        currentUniqueId = uniqueIdProvider.get();
-        logger.info(String.format("Starting game %d with card sets %s, Cardcast %s, %d blanks, %d "
-            + "max players, %d max spectators, %d score limit, players %s, unique %s.",
-            id, options.cardSetIds, cardcastDeckIds, options.blanksInDeck, options.playerLimit,
-            options.spectatorLimit, options.scoreGoal, players, currentUniqueId));
-        // do this stuff outside the players lock; they will lock players again later for much less
-        // time, and not at the same time as trying to lock users, which has caused deadlocks
-        final List<CardSet> cardSets;
-        synchronized (options.cardSetIds) {
-          cardSets = loadCardSets(session);
-          blackDeck = loadBlackDeck(cardSets);
-          whiteDeck = loadWhiteDeck(cardSets);
-        }
-        metrics.gameStart(currentUniqueId, cardSets, options.blanksInDeck, options.playerLimit,
-            options.scoreGoal, !StringUtils.isBlank(options.password));
-        startNextRound();
-        gameManager.broadcastGameListRefresh();
-      }
-      return started;
-    } finally {
-      if (null != session) {
-        session.close();
-      }
     }
+    boolean started;
+    final int numPlayers = players.size();
+    if (numPlayers >= 3) {
+      // Pick a random start judge, though the "next" judge will actually go first.
+      judgeIndex = (int) (Math.random() * numPlayers);
+      started = true;
+    } else {
+      started = false;
+    }
+    if (started) {
+      currentUniqueId = uniqueIdProvider.get();
+      logger.info(String.format("Starting game %d with card sets %s, Cardcast %s, %d blanks, %d "
+          + "max players, %d max spectators, %d score limit, players %s, unique %s.",
+          id, options.cardSetIds, cardcastDeckIds, options.blanksInDeck, options.playerLimit,
+          options.spectatorLimit, options.scoreGoal, players, currentUniqueId));
+      // do this stuff outside the players lock; they will lock players again later for much less
+      // time, and not at the same time as trying to lock users, which has caused deadlocks
+      final List<CardSet> cardSets;
+      synchronized (options.cardSetIds) {
+        cardSets = loadCardSets(session);
+        blackDeck = loadBlackDeck(cardSets);
+        whiteDeck = loadWhiteDeck(cardSets);
+      }
+      metrics.gameStart(currentUniqueId, cardSets, options.blanksInDeck, options.playerLimit,
+          options.scoreGoal, !StringUtils.isBlank(options.password));
+      startNextRound();
+      gameManager.broadcastGameListRefresh();
+    }
+    return started;
   }
 
   public List<CardSet> loadCardSets(final Session session) {

src/main/java/net/socialgamer/cah/handlers/StartGameHandler.java

@@ -80,7 +80,7 @@ public class StartGameHandler extends GameWithPlayerHandler {
         data.put(ErrorInformation.WHITE_CARDS_PRESENT, game.loadWhiteDeck(cardSets).totalCount());
         data.put(ErrorInformation.WHITE_CARDS_REQUIRED, game.getRequiredWhiteCardCount());
         return error(ErrorCode.NOT_ENOUGH_CARDS, data);
-      } else if (!game.start()) {
+      } else if (!game.start(hibernateSession)) {
         return error(ErrorCode.NOT_ENOUGH_PLAYERS);
       } else {
         return data;