读取输入流
我正在使用输入流从网络获取一些数据。我想创建一个日志来检查 InputStream 上是否有内容。 Log("InputStream = "+ is.read()) 我得到 InputStream = 123 但后来当我使用它时，我得到InputStream = -1。我猜想这与迭代器的位置有关，但我在 Java API，您必须使用 reset() （就像使用 mark() 时一样）才能读取再次是输入流。
I am getting some data from network using an Inputstream. I want to make a log to check if the InputStream has something on it. Log("InputStream = "+ is.read()) and I get InputStream = 123
But later when I use it I get InputStream = -1. I guess is something related with the position of the iterator, but I haven't seen in the API of Java that you have to use a reset() (as when you use mark()) to read again the inputStream.
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正确——读给顾客听。一旦使用了流或迭代器，如果不重置它，就无法再次使用它。
Correct - one read to a customer. Once you use a stream or an iterator you can't use it again without resetting it.
InputStream不允许“查看”下一个字符；相反，所有读取方法都会阻塞，直到数据可用为止。如果您需要查看，请使用 Java NIO。
选择器可以告诉您是否有任何通道已准备好数据。InputStreamdoesn't allow to "peek" at the next character; instead, all read methods block until data is available.If you need peeking, use Java NIO. A
Selectorcan tell you if any channel has data ready.您可以将流包装在
PushbackInputStream 中。然后你可以这样做：接下来的读取将重新读取该字符
You could wrap you stream in a
PushbackInputStream. Then you could do this:and a following read will re-read that character
此示例使用
mark()和reset( )重新读取输入流，但它依赖于合适的readlimit的先验知识。根据您的需要，它可能是一种可用的缓冲策略。This example uses
mark()andreset()to re-read the input stream, but it relies on a priori knowledge of a suitablereadlimit. Depending on your needs, it may be a useable buffer strategy.