以多种格式从InputStream读取

Question

I'm trying to write a class that reads HTTP requests and responses and parses them. Since the headers are ordinary text it seemed easiest to read them using a BufferedReader and the readLine method. This obviously won't do for the data body as it may be binary, so I want to switch over to read raw bytes after the headers have been read.

Right now, I'm doing something like this:

InputStream input=socket.getInputStream();
BufferedReader reader=new BufferedReader(new InputStreamReader(input));
BufferedInputStream binstream=new BufferedInputStream(input);

The problem is that the BufferedReader is reading ahead and gobbling up all the binary data from the stream before I have a chance to get at it with the binstream.

Is there a way to prevent it from reading beyond the newline for each call to readLine ? Or is there a better way to read single lines of ASCII text followed raw binary data?

Answer 1

There is already a class in Java for handling HTTP requests and responses. You should use that instead of trying to parse the response on your own. Parsing HTTP response is more difficult than you think as there are different encoding methods that you have to deal with. It isn't really raw binary data in the response payload. The HttpURLConnection class will parse headers for you and give you InputStream for the payload.

http://download.oracle.com/javase/1.4.2/docs/api/java/net/HttpURLConnection.html

Answer 2

If you don't want to use a ready HTTP client/server implementation like Konstantin proposed, DataInputStream has a readLine method. It is deprecated since it isn't doing a proper conversion (mostly a direct byte -> char casting conversion), but I think for pure ASCII header lines you should be good.

(You should put a BufferedInputStream under you DataInputStream, since readLine reads each byte individually.)

Answer 3

commons-httpclient可能会为您节省大量工作。