urlconnectiontest.java

java链接http网页

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

public class URLConnectionTest {

	/**
	 * @param worm
	 */
	public static void main(String[] args) 
	{
		try
		{
			String urlName;
			if(args.length > 0)
				urlName = args[0];
			else
				urlName = "http://www.ynu.edu.cn";
			
			URL url = new URL(urlName);
			URLConnection connection = url.openConnection();
			
			if(args.length > 2)
			{
				String username = args[1];
				String password = args[2];
				String input = username + ":" + password;
				String encoding = base64Encode(input);
				connection.setRequestProperty("Authorization","Basic" + encoding);
			}
			
			connection.connect();
			
			Map<String, List<String>> headers = connection.getHeaderFields();
			for(Map.Entry<String, List<String>> entry : headers.entrySet())
			{
				String key = entry.getKey();
				for(String value : entry.getValue())
					System.out.println(key + ": " + value);
			}
			
			System.out.println("----------");
			System.out.println("getContentType: " + connection.getContentType());
			System.out.println("getContentLength: " + connection.getContentLength());
			System.out.println("getContentEncoding: " + connection.getContentEncoding());
			System.out.println("getDate: " + connection.getDate());
			System.out.println("getExpiration: " + connection.getExpiration());
			System.out.println("getLastModifed: " + connection.getLastModified());
			System.out.println("----------");
			
			Scanner in = new Scanner(connection.getInputStream());
			
			while (in.hasNextLine())
				System.out.println(in.nextLine());
			if (in.hasNextLine()) System.out.println(". . .");
		}
		catch (IOException e)
		{
			e.printStackTrace();
		}
	}
	
	public static String base64Encode(String s)
	{
		ByteArrayOutputStream bOut = new ByteArrayOutputStream();
		Base64OutputStream out = new Base64OutputStream(bOut);
		try
		{
			out.write(s.getBytes());
			out.flush();
		}
		catch (IOException e)
		{
			
		}
		return bOut.toString();
	}

}

class Base64OutputStream extends FilterOutputStream
{
	public Base64OutputStream(OutputStream out)
	{
		super(out);
		
	}
	
	public void write(int c) throws IOException
	{
		inbuf[i] = c;
		i++;
		if (i == 3)
		{
			super.write(toBase64[(inbuf[0]) & 0xFC >> 2]);
			super.write(toBase64[((inbuf[0] & 0x03) << 4) | ((inbuf[1] & 0xF0) >> 4)]);
			super.write(toBase64[((inbuf[1] & 0x0F) << 2) | ((inbuf[2] & 0xC0) >> 6)]);
			super.write(toBase64[inbuf[2] & 0x3F]);
			col += 4;
			i = 0;
			if (col >= 76)
			{
				super.write('\n');
				col = 0;
			}
		}
	}
	
	public void flush() throws IOException
	{
		if(i == 1)
		{
			super.write(toBase64[(inbuf[0]) & 0xFC >> 2]);
			super.write(toBase64[(inbuf[0]) & 0x03 << 4]);
			super.write('=');
			super.write('=');
		}
		else if (i ==2)
		{
			super.write(toBase64[(inbuf[0]) & 0xFC >> 2]);
			super.write(toBase64[((inbuf[0] & 0x03) << 4) | ((inbuf[1] & 0xF0) >> 4)]);
			super.write(toBase64[((inbuf[1] & 0x0F) << 2)]);
			super.write('=');
		}
	}
	
	private static char[] toBase64 =
	{
		'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
		'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
		'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
		'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
	};
	
	private int col = 0;
	private int i = 0;
	private int[] inbuf = new int[3];
}