You'll recall from previous articles in this series that closures are commonly used with iterator methods applied to List and Map collections.
您会回忆起这个系列以前的文章中,闭包一般用于在List和map集合上应用的迭代器方法上。
You cannot perform a join or a union or any other set-operation and map to a target list.
您不能执行一个联接或合并或任何其他组合操作并映射到一个目标列表。
Listing 4 illustrates applying the collect method to a List and a Map.
清单4演示了把collect方法应用于List和Map。
应用推荐