| /* URLEncoder.java -- Class to convert strings to a properly encoded URL |
| Copyright (C) 1998, 1999, 2001, 2002 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.net; |
| |
| import java.io.UnsupportedEncodingException; |
| |
| /* |
| * Written using on-line Java Platform 1.2/1.4 API Specification, as well |
| * as "The Java Class Libraries", 2nd edition (Addison-Wesley, 1998). |
| * Status: Believed complete and correct. |
| */ |
| |
| /** |
| * This utility class contains static methods that converts a |
| * string into a fully encoded URL string in x-www-form-urlencoded |
| * format. This format replaces certain disallowed characters with |
| * encoded equivalents. All upper case and lower case letters in the |
| * US alphabet remain as is, the space character (' ') is replaced with |
| * '+' sign, and all other characters are converted to a "%XX" format |
| * where XX is the hexadecimal representation of that character in a |
| * certain encoding (by default "UTF-8"). |
| * <p> |
| * This method is very useful for encoding strings to be sent to CGI scripts |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Warren Levy <warrenl@cygnus.com> |
| * @author Mark Wielaard (mark@klomp.org) |
| */ |
| public class URLEncoder |
| { |
| /** |
| * This method translates the passed in string into x-www-form-urlencoded |
| * format using the standard "UTF-8" character encoding to hex-encode the |
| * unsafe characters. |
| * |
| * @param s The String to convert |
| * |
| * @return The converted String |
| */ |
| public static String encode(String s) |
| { |
| try |
| { |
| return encode(s, "UTF-8"); |
| } |
| catch (UnsupportedEncodingException uee) |
| { |
| // Should never happen since UTF-8 should always be supported |
| return s; |
| } |
| } |
| |
| /** |
| * This method translates the passed in string into x-www-form-urlencoded |
| * format using the character encoding to hex-encode the unsafe characters. |
| * |
| * @param s The String to convert |
| * @param encoding The encoding to use for unsafe characters |
| * |
| * @return The converted String |
| * |
| * @exception UnsupportedEncodingException If the named encoding is not |
| * supported |
| * |
| * @since 1.4 |
| */ |
| public static String encode(String s, String encoding) |
| throws UnsupportedEncodingException |
| { |
| int length = s.length(); |
| int start = 0; |
| int i = 0; |
| |
| StringBuffer result = new StringBuffer(length); |
| while (true) |
| { |
| while ( i < length && isSafe(s.charAt(i)) ) |
| i++; |
| |
| // Safe character can just be added |
| result.append(s.substring(start, i)); |
| |
| // Are we done? |
| if (i >= length) |
| return result.toString(); |
| else if (s.charAt(i) == ' ') |
| { |
| result.append('+'); // Replace space char with plus symbol. |
| i++; |
| } |
| else |
| { |
| // Get all unsafe characters |
| start = i; |
| char c; |
| while ( i < length && (c = s.charAt(i)) != ' ' && !isSafe(c) ) |
| i++; |
| |
| // Convert them to %XY encoded strings |
| String unsafe = s.substring(start,i); |
| byte bytes[] = unsafe.getBytes(encoding); |
| for (int j = 0; j < bytes.length; j++) |
| { |
| result.append('%'); |
| result.append(Integer.toHexString(((int) bytes[j]) & 0xFF)); |
| } |
| } |
| start = i; |
| } |
| } |
| |
| /** |
| * Private static method that returns true if the given char is either |
| * a uppercase or lowercase letter from 'a' till 'z', or a digit froim |
| * '0' till '9', or one of the characters '-', '_', '.' or '*'. Such |
| * 'safe' character don't have to be url encoded. |
| */ |
| private static boolean isSafe(char c) |
| { |
| return ((c >= 'a' && c <= 'z') || |
| (c >= 'A' && c <= 'Z') || |
| (c >= '0' && c <= '9') || |
| c == '-' || c == '_' || c == '.' || c == '*'); |
| } |
| |
| /** |
| * Private constructor that does nothing. Included to avoid a default |
| * public constructor being created by the compiler. |
| */ |
| private URLEncoder() { } |
| |
| } // class URLEncoder |