server.java

SSD8练习1 Server.java 是运用TCP套结字编程一个很好的例子

import java.io.*;
import java.net.*;
import java.util.*;

public class Server {

	/* Standard input stream */
	private static BufferedReader stdIn = new BufferedReader(
			new InputStreamReader(System.in));

	/* Standard output stream */
	private static PrintWriter stdOut = new PrintWriter(System.out, true);

	/* Standard error stream */
	private static PrintWriter stdErr = new PrintWriter(System.err, true);

	private static String CRLF = "\r\n";

	public static void main(String args[]) throws Exception {

		/* Create a server socket to respond to the clients' responds. */
		String request = "";
		ServerSocket welcomeSocket = new ServerSocket(8000);
		
		/* always ready to receive request */
		while (true) {
			
			/* Accept the client's socket connection. */
			Socket connection = welcomeSocket.accept();
			
			BufferedReader in = new BufferedReader(new InputStreamReader(
					connection.getInputStream()));
			DataOutputStream out = new DataOutputStream(connection
					.getOutputStream());

			request = in.readLine();

			StringTokenizer st = new StringTokenizer(request);

			String token = st.nextToken();
			token = token.toUpperCase();
			if (token.equals("GET")) {
				String filename = st.nextToken();
				if (filename.startsWith("/") == true)
					filename = filename.substring(1);
				filename = "C:\\" + filename;
				//filename.toUpperCase();

				/* Construct a FileInputStream object to read the file */
				File file = new File(filename);
				int numOfBytes = (int) file.length();
				FileInputStream fileIn = new FileInputStream(filename);

				byte fileBytes[] = new byte[numOfBytes];

				fileIn.read(fileBytes, 0, numOfBytes);

				/* judge the requested file's name */
				out.writeBytes("HTTP/1.0 200 Document Follows" + CRLF);
				filename.toUpperCase();
				if (filename.endsWith(".JPG")) {
					out.writeBytes("Content-type: image/jpeg" + CRLF);
				} else if (filename.endsWith(".GIF")) {
					out.writeBytes("Content-type: image/gif" + CRLF);
				} else if (filename.endsWith(".HTM")
						|| filename.endsWith(".HTML")) {
					out.writeBytes("Content-type: docment/htm/html" + CRLF);
				}

				/* write to the client */
				out.writeBytes("Content-Length: " + numOfBytes + CRLF + CRLF);
				/* write file content to client */
				out.write(fileBytes, 0, numOfBytes);

			} else if (token == "PUT") {

			} else {

			}

			in.close();
			out.close();
			connection.close();

		}
	}

}