A Simple Http Server with Java/Socket?

Question

I am currently creating a small HTTP server that returns a static page <p>Hello!</p>... I tried with sockets with Java:

  public static void main(String[] args) throws Exception {          // création de la socket         int port = 1989;         ServerSocket serverSocket = new ServerSocket(port);         System.err.println("Serveur lancé sur le port : " + port);          // repeatedly wait for connections, and process         while (true) {              // on reste bloqué sur l'attente d'une demande client             Socket clientSocket = serverSocket.accept();             System.err.println("Nouveau client connecté");              // on ouvre un flux de converation             BufferedReader in = new BufferedReader(                            new InputStreamReader(clientSocket.getInputStream())                           );              PrintWriter out = new PrintWriter(                          new BufferedWriter(                             new OutputStreamWriter(clientSocket.getOutputStream())),                           true);                 // chaque fois qu'une donnée est lue sur le réseau on la renvoi sur le flux d'écriture.             // la donnée lue est donc retournée exactement au même client.             String s;             while ((s = in.readLine()) != null) {                 System.out.println(s);          out.write("HTTP/1.0 200 OK\r\n");        out.write("Date: Fri, 31 Dec 1999 23:59:59 GMT\r\n");        out.write("Server: Apache/0.8.4\r\n");        out.write("Content-Type: text/html\r\n");        out.write("Content-Length: 59\r\n");        out.write("Expires: Sat, 01 Jan 2000 00:59:59 GMT\r\n");        out.write("Last-modified: Fri, 09 Aug 1996 14:21:40 GMT\r\n");        out.write("\r\n");        out.write("<TITLE>Exemple</TITLE>");        out.write("<P>Ceci est une page d'exemple.</P>");   }              // on ferme les flux.             System.err.println("Connexion avec le client terminée");             out.close();             in.close();             clientSocket.close();         }     } 

this code does not contain any errors and I got a response from the browser like this:

GET / HTTP/1.1 Host: localhost:1989 Connection: keep-alive User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.46 Safari/536.5 Comodo_Dragon/19.0.3.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Encoding: gzip,deflate,sdch Accept-Language: fr-FR,fr;q=0.8,en-US;q=0.6,en;q=0.4 Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3 

But my problem is that I get no page at the Browser? Any help please?

PS: I already read this article: http://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol , (im sorry for the french language...)

Answer 1

In addition to the \r\n after every request header line, you have to send an empty line after the header. Example:

out.write("HTTP/1.0 200 OK\r\n"); // Header... out.write("Last-modified: Fri, 09 Aug 1996 14:21:40 GMT\r\n"); out.write("\r\n"); // The content starts afters this empty line out.write("<TITLE>Hello!</TITLE>"); // Content... 

I corrected your code so that it works (but it is still not perfect, you should handle every request in a seperate thread, e.g. with java.util.concurrent.ThreadPoolExecutor):

public static void main(String[] args) throws Exception {     // création de la socket     int port = 1989;     ServerSocket serverSocket = new ServerSocket(port);     System.err.println("Serveur lancé sur le port : " + port);      // repeatedly wait for connections, and process     while (true) {         // on reste bloqué sur l'attente d'une demande client         Socket clientSocket = serverSocket.accept();         System.err.println("Nouveau client connecté");          // on ouvre un flux de converation          BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));         BufferedWriter out = new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream()));          // chaque fois qu'une donnée est lue sur le réseau on la renvoi sur         // le flux d'écriture.         // la donnée lue est donc retournée exactement au même client.         String s;         while ((s = in.readLine()) != null) {             System.out.println(s);             if (s.isEmpty()) {                 break;             }         }          out.write("HTTP/1.0 200 OK\r\n");         out.write("Date: Fri, 31 Dec 1999 23:59:59 GMT\r\n");         out.write("Server: Apache/0.8.4\r\n");         out.write("Content-Type: text/html\r\n");         out.write("Content-Length: 59\r\n");         out.write("Expires: Sat, 01 Jan 2000 00:59:59 GMT\r\n");         out.write("Last-modified: Fri, 09 Aug 1996 14:21:40 GMT\r\n");         out.write("\r\n");         out.write("<TITLE>Exemple</TITLE>");         out.write("<P>Ceci est une page d'exemple.</P>");          // on ferme les flux.         System.err.println("Connexion avec le client terminée");         out.close();         in.close();         clientSocket.close();     } }