### Question:
HintManagerHolder { public static boolean isUseShardingHint() { return null != HINT_MANAGER_HOLDER.get() && HINT_MANAGER_HOLDER.get().isShardingHint(); }  static void setHintManager(final HintManager hintManager); static boolean isUseShardingHint(); static Optional<ShardingValue<?>> getDatabaseShardingValue(final ShardingKey shardingKey); static Optional<ShardingValue<?>> getTableShardingValue(final ShardingKey shardingKey); static boolean isMasterRouteOnly(); static boolean isDatabaseShardingOnly(); static void clear(); static final String DB_TABLE_NAME; static final String DB_COLUMN_NAME; }### Answer:
@Test public void assertsUseShardingHintWithoutAddShardingColumns() { assertFalse(HintManagerHolder.isUseShardingHint()); }
@Test public void assertsUseShardingHintWithoutSetHintManager() { hintManager.close(); assertFalse(HintManagerHolder.isUseShardingHint()); }
@Test public void assertsUseShardingHintWithAddShardingColumns() { hintManager.addDatabaseShardingValue("logicTable", "shardingColumn", 1); assertTrue(HintManagerHolder.isUseShardingHint()); }