Easy way to parse request headers
I need to write custom java http server. So I'm trying to base on this sample : http://java.sun.com/developer/technicalArticles/Networking/Webserver/ . One of the problems is to parse request headers without usage of any built-in function. Exmaple shows this method:
void handleClient() throws IOException {
InputStream is = new BufferedInputStream(s.getInputStream());
PrintStream ps = new PrintStream(s.getOutputStream());
/* we will only block in read for this many milliseconds
* before we fail with java.io.InterruptedIOException,
* at which point we will abandon the connection.
*/
s.setSoTimeout(WebServer.timeout);
s.setTcpNoDelay(true);
/* zero out the buffer from last time */
for (int i = 0; i < BUF_SIZE; i++) {
buf[i] = 0;
}
try {
/* We only support HTTP GET/HEAD, and don't
* support any fancy HTTP options,
* so we're only interested really in
* the first line.
*/
int nread = 0, r = 0;
outerloop:
while (nread < BUF_SIZE) {
r = is.read(buf, nread, BUF_SIZE - nread);
if (r == -1) {
/* EOF */
return;
}
int i = nread;
nread += r;
for (; i < nread; i++) {
if (buf[i] == (byte)'\n' || buf[i] == (byte)'\r') {
/* read one line */
break outerloop;
}
}
}
/* are we doing a GET or just a HEAD */
boolean doingGet;
/* beginning of file name */
int index;
if (buf[0] == (byte)'G' &&
buf[1] == (byte)'E' &&
buf[2] == (byte)'T' &&
buf[3] == (byte)' ') {
doingGet = true;
index = 4;
} else if (buf[0] == (byte)'H' &&
buf[1] == (byte)'E' &&
buf[2] == (byte)'A' &&
buf[3] == (byte)'D' &&
buf[4] == (byte)' ') {
doingGet = false;
index = 5;
} else {
/* we don't support this method */
ps.print("HTTP/1.0 " + HTTP_BAD_METHOD +
" unsupported method type: ");
ps.write(buf, 0, 5);
ps.write(EOL);
ps.flush();
s.close();
return;
}
int i = 0;
/* find the file name, from:
开发者_Go百科 * GET /foo/bar.html HTTP/1.0
* extract "/foo/bar.html"
*/
for (i = index; i < nread; i++) {
if (buf[i] == (byte)' ') {
break;
}
}
String fname = (new String(buf, 0, index,
i-index)).replace('/', File.separatorChar);
if (fname.startsWith(File.separator)) {
fname = fname.substring(1);
}
File targ = new File(WebServer.root, fname);
if (targ.isDirectory()) {
File ind = new File(targ, "index.html");
if (ind.exists()) {
targ = ind;
}
}
boolean OK = printHeaders(targ, ps);
if (doingGet) {
if (OK) {
sendFile(targ, ps);
} else {
send404(targ, ps);
}
}
} finally {
s.close();
}
}
so basically type of request is read using byte bufferedinoutstream. Is there a better, maybe faster way of doing this ? I also need to support POST request.
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