Java Tutorial/Network/Web Page

HTTP Grab with FileChannel

import java.io.FileOutputStream;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.SocketChannel;
public class MainClass {
  public static void main(String[] args) throws IOException {
    URL u = new URL("http://www.jexp.ru");
    String host = u.getHost();
    int port = 80;
    String file = "/";
    SocketAddress remote = new InetSocketAddress(host, port);
    SocketChannel channel = SocketChannel.open(remote);
    FileOutputStream out = new FileOutputStream("yourfile.htm");
    FileChannel localFile = out.getChannel();
    String request = "GET " + file + " HTTP/1.1\r\n" + "User-Agent: HTTPGrab\r\n"
        + "Accept: text/*\r\n" + "Connection: close\r\n" + "Host: " + host + "\r\n" + "\r\n";
    ByteBuffer header = ByteBuffer.wrap(request.getBytes("US-ASCII"));
    channel.write(header);
    ByteBuffer buffer = ByteBuffer.allocate(8192);
    while (channel.read(buffer) != -1) {
      buffer.flip();
      localFile.write(buffer);
      buffer.clear();
    }
    localFile.close();
    channel.close();
  }
}

Save Web page to a file

import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import javax.swing.text.html.parser.DTD;
public class MainClass {
  public static void main(String[] args) {
    try {
      URL u = new URL("http://www.jexp.ru");
      OutputStream out = new FileOutputStream("test.htm");
      InputStream in = u.openStream();
      DTD html = DTD.getDTD("html");
      System.out.println(html.getName());
      in.close();
      out.flush();
      out.close();
    } catch (Exception e) {
      System.err.println("Usage: java PageSaver url local_file");
    }
  }
}