browser.java

java应用开发详解

import java.io.*;
import java.net.*;
//import java.security.*;

public class Browser 
{
  String urlString;
  public static void main(String[] args) throws Exception 
  {
     if(args.length != 1) 
     {
      	System.out.println("Usage: java Browser url");
      	System.exit(1);
     }
     Browser browser = new Browser(args[0]);
     browser.run();
  }

  public Browser(String urlString) 
  {
     this.urlString = urlString;
  }

  public void run() throws Exception 
  {
     URL url = new URL(urlString);
     HttpURLConnection urlc = (HttpURLConnection) url.openConnection();
     System.out.println("THE HEADERS");
     System.out.println("-----------");
     for(int i=1;;++i) 
     {
       String key;
       String value;
       if((key = urlc.getHeaderFieldKey(i)) == null) break;
       if((value = urlc.getHeaderField(i)) == null) break;
       System.out.print(key);
       System.out.println(" is: " + value);
     }
     BufferedReader reader = new BufferedReader(
     	new InputStreamReader(urlc.getInputStream()));
     String line;
     System.out.println("-----CONTENT------");
     while((line = reader.readLine()) != null) System.out.println(line);
  }
}