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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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package jakarta.servlet.http;

import java.io.IOException;
import java.util.Arrays;
import java.util.Hashtable;
import java.util.ResourceBundle;
import java.util.StringTokenizer;

import jakarta.servlet.ServletInputStream;

Deprecated: As of Java(tm) Servlet API 2.3. These methods were only useful with the default encoding and have been moved to the request interfaces.
/** * @deprecated As of Java(tm) Servlet API 2.3. * These methods were only useful * with the default encoding and have been moved * to the request interfaces. */
@Deprecated public class HttpUtils { private static final String LSTRING_FILE = "jakarta.servlet.http.LocalStrings"; private static final ResourceBundle lStrings = ResourceBundle.getBundle(LSTRING_FILE);
Constructs an empty HttpUtils object.
/** * Constructs an empty <code>HttpUtils</code> object. * */
public HttpUtils() { // NOOP }
Parses a query string passed from the client to the server and builds a HashTable object with key-value pairs. The query string should be in the form of a string packaged by the GET or POST method, that is, it should have key-value pairs in the form key=value, with each pair separated from the next by a & character.

A key can appear more than once in the query string with different values. However, the key appears only once in the hashtable, with its value being an array of strings containing the multiple values sent by the query string.

The keys and values in the hashtable are stored in their decoded form, so any + characters are converted to spaces, and characters sent in hexadecimal notation (like %xx) are converted to ASCII characters.

Params:
  • s – a string containing the query to be parsed
Throws:
Returns: a HashTable object built from the parsed key-value pairs
/** * * Parses a query string passed from the client to the * server and builds a <code>HashTable</code> object * with key-value pairs. * The query string should be in the form of a string * packaged by the GET or POST method, that is, it * should have key-value pairs in the form <i>key=value</i>, * with each pair separated from the next by a &amp; character. * * <p>A key can appear more than once in the query string * with different values. However, the key appears only once in * the hashtable, with its value being * an array of strings containing the multiple values sent * by the query string. * * <p>The keys and values in the hashtable are stored in their * decoded form, so * any + characters are converted to spaces, and characters * sent in hexadecimal notation (like <i>%xx</i>) are * converted to ASCII characters. * * @param s a string containing the query to be parsed * * @return a <code>HashTable</code> object built * from the parsed key-value pairs * * @exception IllegalArgumentException if the query string * is invalid * */
public static Hashtable<String,String[]> parseQueryString(String s) { String valArray[] = null; if (s == null) { throw new IllegalArgumentException(); } Hashtable<String,String[]> ht = new Hashtable<>(); StringBuilder sb = new StringBuilder(); StringTokenizer st = new StringTokenizer(s, "&"); while (st.hasMoreTokens()) { String pair = st.nextToken(); int pos = pair.indexOf('='); if (pos == -1) { // XXX // should give more detail about the illegal argument 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[] = ht.get(key); valArray = Arrays.copyOf(oldVals, oldVals.length + 1); valArray[oldVals.length] = val; } else { valArray = new String[1]; valArray[0] = val; } ht.put(key, valArray); } return ht; }
Parses data from an HTML form that the client sends to the server using the HTTP POST method and the application/x-www-form-urlencoded MIME type.

The data sent by the POST method contains key-value pairs. A key can appear more than once in the POST data with different values. However, the key appears only once in the hashtable, with its value being an array of strings containing the multiple values sent by the POST method.

The keys and values in the hashtable are stored in their decoded form, so any + characters are converted to spaces, and characters sent in hexadecimal notation (like %xx) are converted to ASCII characters.

Params:
  • len – an integer specifying the length, in characters, of the ServletInputStream object that is also passed to this method
  • in – the ServletInputStream object that contains the data sent from the client
Throws:
Returns: a HashTable object built from the parsed key-value pairs
/** * * Parses data from an HTML form that the client sends to * the server using the HTTP POST method and the * <i>application/x-www-form-urlencoded</i> MIME type. * * <p>The data sent by the POST method contains key-value * pairs. A key can appear more than once in the POST data * with different values. However, the key appears only once in * the hashtable, with its value being * an array of strings containing the multiple values sent * by the POST method. * * <p>The keys and values in the hashtable are stored in their * decoded form, so * any + characters are converted to spaces, and characters * sent in hexadecimal notation (like <i>%xx</i>) are * converted to ASCII characters. * * * * @param len an integer specifying the length, * in characters, of the * <code>ServletInputStream</code> * object that is also passed to this * method * * @param in the <code>ServletInputStream</code> * object that contains the data sent * from the client * * @return a <code>HashTable</code> object built * from the parsed key-value pairs * * * @exception IllegalArgumentException if the data * sent by the POST method is invalid * */
public static Hashtable<String,String[]> parsePostData(int len, ServletInputStream in) { // XXX // should a length of 0 be an IllegalArgumentException // cheap hack to return an empty hash if (len <=0) return new Hashtable<>(); if (in == null) { throw new IllegalArgumentException(); } // Make sure we read the entire POSTed body. 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(), e); } // XXX we shouldn't assume that the only kind of POST body // is FORM data encoded using ASCII or ISO Latin/1 ... or // that the body should always be treated as FORM data. try { String postedBody = new String(postedBytes, 0, len, "8859_1"); return parseQueryString(postedBody); } catch (java.io.UnsupportedEncodingException e) { // XXX function should accept an encoding parameter & throw this // exception. Otherwise throw something expected. throw new IllegalArgumentException(e.getMessage(), e); } } /* * Parse a name in the query string. */ private static String parseName(String s, StringBuilder 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) { // XXX // need to be more specific about illegal arg throw new IllegalArgumentException(); } catch (StringIndexOutOfBoundsException e) { String rest = s.substring(i); sb.append(rest); if (rest.length()==2) i++; } break; default: sb.append(c); break; } } return sb.toString(); }
Reconstructs the URL the client used to make the request, using information in the HttpServletRequest object. The returned URL contains a protocol, server name, port number, and server path, but it does not include query string parameters.

Because this method returns a StringBuffer, not a string, you can modify the URL easily, for example, to append query parameters.

This method is useful for creating redirect messages and for reporting errors.

Params:
  • req – a HttpServletRequest object containing the client's request
Returns: a StringBuffer object containing the reconstructed URL
/** * * Reconstructs the URL the client used to make the request, * using information in the <code>HttpServletRequest</code> object. * The returned URL contains a protocol, server name, port * number, and server path, but it does not include query * string parameters. * * <p>Because this method returns a <code>StringBuffer</code>, * not a string, you can modify the URL easily, for example, * to append query parameters. * * <p>This method is useful for creating redirect messages * and for reporting errors. * * @param req a <code>HttpServletRequest</code> object * containing the client's request * * @return a <code>StringBuffer</code> object containing * the reconstructed URL * */
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); // http, https 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; } }