如果有問題，請與我聯系。 參考資料 java.util.regex的幫助文檔

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

/**
   This program displays all URLs in a web page

   by jgyang 2005-11-18

*/
public class HerfMatch
{
   public static void main(String[] args)
   {
      try
      {
         String urlString = "http://www.tom.com";

         InputStreamReader in = new InputStreamReader(
            new URL(urlString).openStream());

         StringBuffer input = new StringBuffer();
         int ch;
         while ((ch = in.read()) != -1) input.append((char)ch);

         String patternString
    = "<a\\s+href\\s*=\\s*(\"[^\"]*\"|[^\\s>]|\"[^\"]*\"\\s*+[^>\"]*\\s*=\\s*(\"[^\"]*\"|[^\\s>]))\\s*>";
            Pattern pattern = Pattern.compile(patternString,
            Pattern.CASE_INSENSITIVE);
         Matcher matcher = pattern.matcher(input);

         int i = 0;
         while (matcher.find())
         {
            int start = matcher.start();
            int end = matcher.end();
            String match = input.substring(start, end);
            System.out.println(++i + " : " + match);
         }
      }
      catch (IOException exception)
      {
         exception.printStackTrace();
      }
      catch (PatternSyntaxException exception)
      {
         exception.printStackTrace();
      }
   }
}