A stream is a highly abstracted metaphor and a strict contract. It means that you can manipulate objects in sequence without concern about gaps. That is to say, a stream must have no vacuum or gaps. Objects in it are arranged in sequence one by one continuously. As a result, we don't have to worry about encountering a vacuum abruptly in the midst of processing a stream, or we can't leave a vacuum deliberately when producing a stream. In other words, we don't have to consider the case of a void in processing or producing a stream. There is no way we can come across it or produce it on purpose. If you are constructing a stream, you must not leave any gaps in the stream.

换句话说，如果有一个缺口，它一定不是一个流。当您将序列称为流时，要么您被保证其中没有空白，要么您必须信守您所生成的序列中没有空白的承诺。

回顾一下，想象一条水流。它最大的特点是什么?

连续!

溪流的抽象精神就是关于它的。

另一点(对于读取文件的情况):

流可以允许您在完成读取文件的所有内容之前执行其他操作。 可以节省内存，因为不需要一次加载所有文件内容。

我所见过的关于流的最好解释是SICP的第3章。(你可能需要阅读前两章才能理解，但无论如何你都应该这样做。: -)

它们对字节根本不使用sterams，而是整数。我从中得到的要点是:

流是延迟列表 在某些情况下，急于提前计算所有内容的计算开销是惊人的 我们可以用流来表示无限长的序列

A stream is a highly abstracted metaphor and a strict contract. It means that you can manipulate objects in sequence without concern about gaps. That is to say, a stream must have no vacuum or gaps. Objects in it are arranged in sequence one by one continuously. As a result, we don't have to worry about encountering a vacuum abruptly in the midst of processing a stream, or we can't leave a vacuum deliberately when producing a stream. In other words, we don't have to consider the case of a void in processing or producing a stream. There is no way we can come across it or produce it on purpose. If you are constructing a stream, you must not leave any gaps in the stream.

换句话说，如果有一个缺口，它一定不是一个流。当您将序列称为流时，要么您被保证其中没有空白，要么您必须信守您所生成的序列中没有空白的承诺。

回顾一下，想象一条水流。它最大的特点是什么?

连续!

溪流的抽象精神就是关于它的。

我使用的可视化是传送带，不是在真实的工厂里，因为我对此一无所知，而是在卡通工厂里，物品沿着线移动，被盖章、装箱、计数和检查，由一系列愚蠢的设备完成。

你有做一件事的简单组件，例如一个把樱桃放在蛋糕上的设备。这个设备有一个无樱桃蛋糕的输入流，和一个有樱桃蛋糕的输出流。用这种方式组织处理有三个优点值得一提。

首先，它简化了组件本身:如果你想把巧克力糖衣放在蛋糕上，你不需要一个复杂的设备，知道蛋糕的一切，你可以创造一个愚蠢的设备，把巧克力糖衣粘在任何东西上(在漫画中，这甚至不知道下一个东西不是蛋糕，而是怀尔E.大狼)。

其次，你可以通过将这些设备按不同的顺序排列来创造不同的产品:也许你想让你的蛋糕在樱桃上放糖衣，而不是樱桃在糖衣上，你可以简单地通过在生产线上交换设备来做到这一点。

Thirdly, the devices don't need to manage inventory, boxing, or unboxing. The most efficient way of aggregating and packaging things is changeable: maybe today you're putting your cakes into boxes of 48 and sending them out by the truckload, but tomorrow you want to send out boxes of six in response to custom orders. This kind of change can be accommodated by replacing or reconfiguring the machines at the start and end of the production line; the cherry machine in the middle of the line doesn't have to be changed to process a different number of items at a time, it always works with one item at a time and it doesn't have to know how its input or output is being grouped.

我认为您需要考虑后备存储本身通常只是另一种抽象。内存流很容易理解，但是文件完全不同，这取决于您使用的文件系统，而不考虑您使用的是什么硬盘驱动器。事实上，并不是所有的流都位于备份存储的顶部:网络流基本上就是流。

流的意义在于我们将注意力限制在重要的事情上。通过标准抽象，我们可以执行公共操作。例如，即使您今天不想在文件或HTTP响应中搜索url，也不意味着您明天就不想这样做了。

Streams were originally conceived when memory was tiny compared to storage. Just reading a C file could be a significant load. Minimizing the memory footprint was extremely important. Hence, an abstraction in which very little needed to be loaded was very useful. Today, it is equally useful when performing network communication and, it turns out, rarely that restrictive when we deal with files. The ability to transparently add things like buffering in a general fashion makes it even more useful.