Http Server : Web Server « Tiny Application « Java

Http Server

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.StringTokenizer;

public class httpServer {
  public static void main(String args[]) {
    int port;
    ServerSocket server_socket;
    try {
      port = Integer.parseInt(args[0]);
    } catch (Exception e) {
      port = 1500;
    }
    try {

      server_socket = new ServerSocket(port);
      System.out.println("httpServer running on port "
          + server_socket.getLocalPort());

      // server infinite loop
      while (true) {
        Socket socket = server_socket.accept();
        System.out.println("New connection accepted "
            + socket.getInetAddress() + ":" + socket.getPort());

        // Construct handler to process the HTTP request message.
        try {
          httpRequestHandler request = new httpRequestHandler(socket);
          // Create a new thread to process the request.
          Thread thread = new Thread(request);

          // Start the thread.
          thread.start();
        } catch (Exception e) {
          System.out.println(e);
        }
      }
    } catch (IOException e) {
      System.out.println(e);
    }
  }
}

class httpRequestHandler implements Runnable {
  final static String CRLF = "\r\n";

  Socket socket;

  InputStream input;

  OutputStream output;

  BufferedReader br;

  public httpRequestHandler(Socket socket) throws Exception {
    this.socket = socket;
    this.input = socket.getInputStream();
    this.output = socket.getOutputStream();
    this.br = new BufferedReader(new InputStreamReader(socket
        .getInputStream()));
  }

  public void run() {
    try {
      processRequest();
    } catch (Exception e) {
      System.out.println(e);
    }
  }

  private void processRequest() throws Exception {
    while (true) {

      String headerLine = br.readLine();
      System.out.println(headerLine);
      if (headerLine.equals(CRLF) || headerLine.equals(""))
        break;

      StringTokenizer s = new StringTokenizer(headerLine);
      String temp = s.nextToken();

      if (temp.equals("GET")) {

        String fileName = s.nextToken();
        fileName = "." + fileName;

        FileInputStream fis = null;
        boolean fileExists = true;
        try {
          fis = new FileInputStream(fileName);
        } catch (FileNotFoundException e) {
          fileExists = false;
        }
        String serverLine = "Server: Simple Java Http Server";
        String statusLine = null;
        String contentTypeLine = null;
        String entityBody = null;
        String contentLengthLine = "error";
        if (fileExists) {
          statusLine = "HTTP/1.0 200 OK" + CRLF;
          contentTypeLine = "Content-type: " + contentType(fileName)
              + CRLF;
          contentLengthLine = "Content-Length: "
              + (new Integer(fis.available())).toString() + CRLF;
        } else {
          statusLine = "HTTP/1.0 404 Not Found" + CRLF;
          contentTypeLine = "text/html";
          entityBody = "<HTML>"
              + "<HEAD><TITLE>404 Not Found</TITLE></HEAD>"
              + "<BODY>404 Not Found"
              + "<br>usage:http://yourHostName:port/"
              + "fileName.html</BODY></HTML>";
        }

        // Send the status line.
        output.write(statusLine.getBytes());
        System.out.println(statusLine);

        // Send the server line.
        output.write(serverLine.getBytes());
        System.out.println(serverLine);

        // Send the content type line.
        output.write(contentTypeLine.getBytes());
        System.out.println(contentTypeLine);

        // Send the Content-Length
        output.write(contentLengthLine.getBytes());
        System.out.println(contentLengthLine);

        // Send a blank line to indicate the end of the header lines.
        output.write(CRLF.getBytes());
        System.out.println(CRLF);

        // Send the entity body.
        if (fileExists) {
          sendBytes(fis, output);
          fis.close();
        } else {
          output.write(entityBody.getBytes());
        }

      }
    }

    try {
      output.close();
      br.close();
      socket.close();
    } catch (Exception e) {
    }
  }

  private static void sendBytes(FileInputStream fis, OutputStream os)
      throws Exception {

    byte[] buffer = new byte[1024];
    int bytes = 0;

    while ((bytes = fis.read(buffer)) != -1) {
      os.write(buffer, 0, bytes);
    }
  }

  private static String contentType(String fileName) {
    if (fileName.endsWith(".htm") || fileName.endsWith(".html")
        || fileName.endsWith(".txt")) {
      return "text/html";
    } else if (fileName.endsWith(".jpg") || fileName.endsWith(".jpeg")) {
      return "image/jpeg";
    } else if (fileName.endsWith(".gif")) {
      return "image/gif";
    } else {
      return "application/octet-stream";
    }
  }
}
Http Server : Web Server « Tiny Application « Java

Related examples in the same category
