Servlet--HttpUtils类

定义

收集 HTTP Servlet 使用的静态的有效的方法。

当查询字符串无效时，该方法抛出一个 IllegalArgumentException。

这个类我从来没接触过，不过既然是一个工具类，就贴出来吧，下面是源码：

package javax.servlet.http;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Hashtable;
import java.util.ResourceBundle;
import java.util.StringTokenizer;
import javax.servlet.ServletInputStream;

/** @deprecated */
public class HttpUtils
{
  private static final String LSTRING_FILE = "javax.servlet.http.LocalStrings";
  private static ResourceBundle lStrings = ResourceBundle.getBundle("javax.servlet.http.LocalStrings");

  public static Hashtable parseQueryString(String s)
  {
    String[] valArray = null;

    if (s == null) {
      throw new IllegalArgumentException();
    }
    Hashtable ht = new Hashtable();
    StringBuffer sb = new StringBuffer();
    StringTokenizer st = new StringTokenizer(s, "&");
    while (st.hasMoreTokens()) {
      String pair = st.nextToken();
      int pos = pair.indexOf('=');
      if (pos == -1)
      {
        throw new IllegalArgumentException();
      }
      String key = parseName(pair.substring(0, pos), sb);
      String val = parseName(pair.substring(pos + 1, pair.length()), sb);
      if (ht.containsKey(key)) {
        String[] oldVals = (String[])(String[])ht.get(key);
        valArray = new String[oldVals.length + 1];
        for (int i = 0; i < oldVals.length; i++)
          valArray[i] = oldVals[i];
        valArray[oldVals.length] = val;
      } else {
        valArray = new String[1];
        valArray[0] = val;
      }
      ht.put(key, valArray);
    }
    return ht;
  }

  public static Hashtable parsePostData(int len, ServletInputStream in)
  {
    if (len <= 0) {
      return new Hashtable();
    }
    if (in == null) {
      throw new IllegalArgumentException();
    }

    byte[] postedBytes = new byte[len];
    try {
      int offset = 0;
      do
      {
        int inputLen = in.read(postedBytes, offset, len - offset);
        if (inputLen <= 0) {
          String msg = lStrings.getString("err.io.short_read");
          throw new IllegalArgumentException(msg);
        }
        offset += inputLen;
      }while (len - offset > 0);
    }
    catch (IOException e) {
      throw new IllegalArgumentException(e.getMessage());
    }

    try
    {
      String postedBody = new String(postedBytes, 0, len, "8859_1");
      return parseQueryString(postedBody);
    }
    catch (UnsupportedEncodingException e) {
    }
    throw new IllegalArgumentException(e.getMessage());
  }

  private static String parseName(String s, StringBuffer sb)
  {
    sb.setLength(0);
    for (int i = 0; i < s.length(); i++) {
      char c = s.charAt(i);
      switch (c) {
      case '+':
        sb.append(' ');
        break;
      case '%':
        try {
          sb.append((char)Integer.parseInt(s.substring(i + 1, i + 3), 16));

          i += 2;
        }
        catch (NumberFormatException e)
        {
          throw new IllegalArgumentException();
        } catch (StringIndexOutOfBoundsException e) {
          String rest = s.substring(i);
          sb.append(rest);
          if (rest.length() == 2) {
            i++;
          }
        }

      default:
        sb.append(c);
      }
    }

    return sb.toString();
  }

  public static StringBuffer getRequestURL(HttpServletRequest req)
  {
    StringBuffer url = new StringBuffer();
    String scheme = req.getScheme();
    int port = req.getServerPort();
    String urlPath = req.getRequestURI();

    url.append(scheme);
    url.append("://");
    url.append(req.getServerName());
    if (((scheme.equals("http")) && (port != 80)) || ((scheme.equals("https")) && (port != 443)))
    {
      url.append(':');
      url.append(req.getServerPort());
    }

    url.append(urlPath);
    return url;
  }
}

Servlet--HttpUtils类

原文：http://blog.csdn.net/u011794238/article/details/46505415