code: public V put(ResourceType type, PoolInfo poolInfo, V value) {
      Map<PoolInfo, V> poolInfoMap = typePoolInfoMap.get(type);
      if (poolInfoMap == null) {
        poolInfoMap = new HashMap<PoolInfo, V>();
        typePoolInfoMap.put(type, poolInfoMap);
      }
      return poolInfoMap.put(poolInfo, value);
    }
docs: Put the value with the appropriate keys
  
  @param type Resource type
  @param poolInfo Pool info
  @param value Value to put
  @return Previous value, can be null if wasn't set