javax.servlet.http.HttpUtils Maven / Gradle / Ivy
/*
* 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package javax.servlet.http;
import java.io.IOException;
import java.util.Hashtable;
import java.util.ResourceBundle;
import java.util.StringTokenizer;
import javax.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.
*/
@SuppressWarnings("dep-ann") // Spec API does not use @Deprecated
public class HttpUtils {
private static final String LSTRING_FILE =
"javax.servlet.http.LocalStrings";
private static final ResourceBundle lStrings =
ResourceBundle.getBundle(LSTRING_FILE);
/**
* Constructs an empty HttpUtils 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.
*
* @param s a string containing the query to be parsed
*
* @return a HashTable object built
* from the parsed key-value pairs
*
* @exception IllegalArgumentException if the query string
* is invalid
*
*/
public static Hashtable parseQueryString(String s) {
String valArray[] = null;
if (s == null) {
throw new IllegalArgumentException();
}
Hashtable 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 = 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;
}
/**
*
* 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.
*
*
*
* @param len an integer specifying the length,
* in characters, of the
* ServletInputStream
* object that is also passed to this
* method
*
* @param in the ServletInputStream
* object that contains the data sent
* from the client
*
* @return a HashTable object built
* from the parsed key-value pairs
*
*
* @exception IllegalArgumentException if the data
* sent by the POST method is invalid
*
*/
public static Hashtable 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.
*
* @param req a HttpServletRequest object
* containing the client's request
*
* @return a StringBuffer 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;
}
}