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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.myfaces.shared.renderkit.html.util;
20  
21  import java.io.IOException;
22  import java.io.Writer;
23  
24  /**
25   * Converts characters outside of latin-1 set in a string to numeric character references.
26   * 
27   */
28  public abstract class UnicodeEncoder
29  {
30      /**
31       * Encodes the given string, so that it can be used within a html page.
32       * @param string the string to convert
33       */
34      public static String encode (String string)
35      {
36          if (string == null)
37          {
38              return "";
39          }
40  
41          StringBuilder sb = null;
42          char c;
43          for (int i = 0; i < string.length (); ++i)
44          {
45              c = string.charAt(i);
46              if (((int)c) >= 0x80)
47              {
48                  if( sb == null )
49                  {
50                      sb = new StringBuilder( string.length()+4 );
51                      sb.append( string.substring(0,i) );
52                  }
53                  //encode all non basic latin characters
54                  sb.append("&#");
55                  sb.append((int)c);
56                  sb.append(";");
57              }
58              else if( sb != null )
59              {
60                  sb.append(c);
61              }
62          }
63  
64          return sb != null ? sb.toString() : string;
65      }
66      
67      public static void encode (Writer writer, String string) throws IOException
68      {
69          if (string == null)
70          {
71              return;
72          }
73  
74          int start = 0;
75          char c;
76          for (int i = 0; i < string.length (); ++i)
77          {
78              c = string.charAt(i);
79              if (((int)c) >= 0x80)
80              {
81                  if (start < i)
82                  {
83                      writer.write(string, start, i-start);
84                  }
85                  start = i+1;
86                  //encode all non basic latin characters
87                  writer.write("&#");
88                  writer.write(Integer.toString((int)c));
89                  writer.write(";");
90              }
91          }
92  
93          if (start == 0)
94          {
95              writer.write(string);
96          }
97          else if (start < string.length())
98          {
99              writer.write(string,start,string.length()-start);
100         }
101     }
102 
103     public static void encode (Writer writer, char[] cbuf, int off, int len) throws IOException
104     {
105         if (cbuf == null)
106         {
107             return;
108         }
109 
110         int start = off;
111         char c;
112         for (int i = off; i < off+len; ++i)
113         {
114             c = cbuf[i];
115             if (((int)c) >= 0x80)
116             {
117                 if (start < i)
118                 {
119                     writer.write(cbuf, start, i-start);
120                 }
121                 start = i+1;
122                 //encode all non basic latin characters
123                 writer.write("&#");
124                 writer.write(Integer.toString((int)c));
125                 writer.write(";");
126             }
127         }
128 
129         if (start == off)
130         {
131             writer.write(cbuf, off, len);
132         }
133         else if (start < off+len)
134         {
135             writer.write(cbuf,start,off+len-start);
136         }
137     }
138     
139     public static void encode (Writer writer, String cbuf, int off, int len) throws IOException
140     {
141         if (cbuf == null)
142         {
143             return;
144         }
145 
146         int start = off;
147         char c;
148         for (int i = off; i < off+len; ++i)
149         {
150             c = cbuf.charAt(i);
151             if (((int)c) >= 0x80)
152             {
153                 if (start < i)
154                 {
155                     writer.write(cbuf, start, i-start);
156                 }
157                 start = i+1;
158                 //encode all non basic latin characters
159                 writer.write("&#");
160                 writer.write(Integer.toString((int)c));
161                 writer.write(";");
162             }
163         }
164 
165         if (start == off)
166         {
167             writer.write(cbuf, off, len);
168         }
169         else if (start < off+len)
170         {
171             writer.write(cbuf,start,off+len-start);
172         }
173     }
174 }