001 package com.croftsoft.core.net;
002
003 /*********************************************************************
004 *
005 * Java 1.1 substitute for URLDecoder and URLEncoder.
006 *
007 * <P>
008 *
009 * The classes java.net.URLDecoder and java.net.URLEncoder were not
010 * available until Java 1.2. This class provides a substitute for
011 * those programs which must use the Java 1.1 API.
012 *
013 * <P>
014 *
015 * @see
016 * java.net.URLDecoder
017 * @see
018 * java.net.URLEncoder
019 *
020 * @author
021 * <A HREF="http://www.alumni.caltech.edu/~croft">David W. Croft</A>
022 * @version
023 * 2000-04-21
024 *********************************************************************/
025
026 public final class URLCoder
027 //////////////////////////////////////////////////////////////////////
028 //////////////////////////////////////////////////////////////////////
029 {
030
031 private URLCoder ( ) { }
032
033 //////////////////////////////////////////////////////////////////////
034 //////////////////////////////////////////////////////////////////////
035
036 /*********************************************************************
037 * Displays the encoded value of the first argument.
038 *********************************************************************/
039 public static void main ( String [ ] args )
040 //////////////////////////////////////////////////////////////////////
041 {
042 System.out.println ( encode ( args [ 0 ] ) );
043 }
044
045 /*********************************************************************
046 * Performs the equivalent of java.net.URLDecoder.decode().
047 *********************************************************************/
048 public static String decode ( String s )
049 //////////////////////////////////////////////////////////////////////
050 {
051 if ( s == null )
052 {
053 throw new IllegalArgumentException ( "null" );
054 }
055
056 StringBuffer stringBuffer = new StringBuffer ( );
057
058 int length = s.length ( );
059
060 for ( int i = 0; i < length; i++ )
061 {
062 char c = s.charAt ( i );
063
064 if ( ( ( c >= 'a' ) && ( c <= 'z' ) )
065 || ( ( c >= 'A' ) && ( c <= 'Z' ) )
066 || ( ( c >= '0' ) && ( c <= '9' ) )
067 || ( c == '.' )
068 || ( c == '-' )
069 || ( c == '*' )
070 || ( c == '_' ) )
071 {
072 stringBuffer.append ( c );
073 }
074 else if ( c == '+' )
075 {
076 stringBuffer.append ( ' ' );
077 }
078 else if ( c == '%' )
079 {
080 stringBuffer.append ( ( char )
081 ( 16 * Character.digit ( s.charAt ( ++i ), 16 )
082 + Character.digit ( s.charAt ( ++i ), 16 ) ) );
083 }
084 else
085 {
086 stringBuffer.append ( c );
087 }
088 }
089
090 return stringBuffer.toString ( );
091 }
092
093 /*********************************************************************
094 * Performs the equivalent of java.net.URLEncoder.encode().
095 *********************************************************************/
096 public static String encode ( String s )
097 //////////////////////////////////////////////////////////////////////
098 {
099 if ( s == null )
100 {
101 throw new IllegalArgumentException ( "null" );
102 }
103
104 StringBuffer stringBuffer = new StringBuffer ( );
105
106 int length = s.length ( );
107
108 for ( int i = 0; i < length; i++ )
109 {
110 char c = s.charAt ( i );
111
112 if ( ( ( c >= 'a' ) && ( c <= 'z' ) )
113 || ( ( c >= 'A' ) && ( c <= 'Z' ) )
114 || ( ( c >= '0' ) && ( c <= '9' ) )
115 || ( c == '.' )
116 || ( c == '-' )
117 || ( c == '*' )
118 || ( c == '_' ) )
119 {
120 stringBuffer.append ( c );
121 }
122 else if ( c == ' ' )
123 {
124 stringBuffer.append ( '+' );
125 }
126 else
127 {
128 stringBuffer.append ( "%" + Integer.toHexString (
129 ( ( int ) c ) & 0xFF ).toUpperCase ( ) );
130 }
131 }
132
133 return stringBuffer.toString ( );
134 }
135
136 //////////////////////////////////////////////////////////////////////
137 //////////////////////////////////////////////////////////////////////
138 }