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Small HTTP server using java?

I created the following test server using java:

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

class tcpServer{
    public static void main(String args[]){
        ServerSocket s = null;
        try{
            s = new ServerSocket(7896);
            //right now the stream is open.
            while(true){
                Socket clientSocket = s.accept();
                Connection c = new Connection(clientSocket);
                //now the connection is established
            }
        }catch(IOException e){
            System.out.println("Unable to read: " + e.getMessage());
        }
    }
}
class Connection extends Thread{
    Socket clientSocket;
    BufferedReader din;
    OutputStreamWriter outWriter;

    public Connection(Socket clientSocket){
        try{
            this.clientSocket = clientSocket;
            din = new BufferedReader(new InputStreamReader(clientSocket.getInputStream(), "ASCII"));
            outWriter = new OutputStreamWriter(clientSocket.getOutputStream());
            this.start();
        }catch(IOException e){
            System.out.println("Connection: " + e.getMessage());
        }   
    }
    public void run(){
        try{
        String line = null;
        while((line = din.readLine())!=null){
            System.out.println("Read" + line);
            if(line.length()==0)    
                break;
        }
        //here write the content type etc details:
        System.out.println("Someone connected: " + clientSocket);
        outWriter.write("HTTP/1.1 200 OK\r\n");
        outWriter.write("Date: Tue, 11 Jan 2011 13:09:20 GMT\r\n");
        outWriter.write("Expires: -1\r\n");
        outWriter.write("Cache-Control: private, max-age=0\r\n");
        outWriter.write("Content-type: text/html\r\n");
        outWriter.write("Server: vinit\r\n");
        outWriter.write("X-XSS-Protection: 1; mode=block\r\n");
        outWriter.write("<html><head><title>Hello</title></head><body>Hello world from my server</body></html>\r\n");
        }catch(EOFException e){
            System.out.println("EOF: " + e.getMessage());
        }
        catch(IOException e){
            System.out.println("IO at run: " + e.getMessage());
        }finally{
            try{
                            outWriter.close();  
                clientSocket.close();
            }catch(IOException e){
                System.out.println("Unable to close the socket");
            }
        }
    }
}

Now I want this server to respond to my browser. why I gave the URL: http://localhost:7896 and as a result I get on the server side:

ReadGET / HTTP/1.1
ReadHost: localhost:7896
ReadConnection: keep-alive
ReadCache-Control: max-age=0
ReadAccept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
ReadUser-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10
ReadAccept-Encoding: gzip,deflate,sdch
ReadAccept-Language: en-US,en;q=0.8
ReadAccept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
ReadCookie: test_cookie=test cookie
Read
Someone connected: Socket[addr=/0:0:0:0:0:0:0:1,port=36651,localport=7896]

And the blank white screen in my browser and the source code is also empty. In google chrome browser.

So who can tell me where I am wrong. I'm actually new to this thing. so please correct me.

Thanks in advance

+3
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5 answers

DataOutputStream - writeUTF, , , . DataOutputStream , - writeUTF UTF-8, HTTP CRLF ASCII.

- OutputStreamWriter :

writer.write("HTTP/1.1 200 OK\r\n");
writer.write("Date: Tue, 11 Jan 2011 13:09:20 GMT\r\n");

.

, writeLine , CRLF ( ), .

, .

EDIT: :

-, . , din BufferedReader :

din = new BufferedReader(new InputStreamReader(clientSocket.getInputStream(),
                                               "ASCII"));

, :

String line;
while ((line = din.readLine()) != null) {
    System.out.println("Read " + line);
    if (line.length() == 0) {
        break;
    }
}

EDIT: , HTTP-, PUT/POST ( , ). , .

, , , , - .

.

+5

, HTTP- Java, :

https://github.com/berb/java-web-server

HTTP- Java, . , . . , , , .

​​ \r\n HTML. \r\n . , , Chuncked:

String out = "<html><head><title>Hello</title></head><body>Hello world from my server</body></html>\r\n";

outWriter.write("Content-Length: "+out.getBytes().length+"\r\n\r\n");
outWriter.write(out);
+2
  • HTTP ASCII, , Content-Type. , UTF-8!
  • .
  • Why do you set your Transfert-encoding encoding? Your body is not.
+1
source

Check it out, it's already done for you:

http://www.mcwalter.org/technology/java/httpd/tiny/index.html

0
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I'm not sure if you can use writeUTF instead, you might need to use instead writeBytes. In addition, you need to complete each line with '\n'.

-1
source

Source: https://habr.com/ru/post/1784668/

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