lucene-java-3.5.0/lucene/contrib/highlighter/src/java/org/apache/lucene/search/highlight/SimpleHTMLEncoder.java

   1 package org.apache.lucene.search.highlight;
   2 /**
   3  * Copyright 2005 The Apache Software Foundation
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 /**
  19  * Simple {@link Encoder} implementation to escape text for HTML output
  20  *
  21  */
  22 public class SimpleHTMLEncoder implements Encoder
  23 {
  24         public SimpleHTMLEncoder()
  25         {
  26         }
  27
  28         public String encodeText(String originalText)
  29         {
  30                 return htmlEncode(originalText);
  31         }
  32
  33         /**
  34          * Encode string into HTML
  35          */
  36         public final static String htmlEncode(String plainText)
  37         {
  38                 if (plainText == null || plainText.length() == 0)
  39                 {
  40                         return "";
  41                 }
  42
  43                 StringBuilder result = new StringBuilder(plainText.length());
  44
  45                 for (int index=0; index<plainText.length(); index++)
  46                 {
  47                         char ch = plainText.charAt(index);
  48
  49                         switch (ch)
  50                         {
  51                         case '"':
  52                                 result.append("&quot;");
  53                                 break;
  54
  55                         case '&':
  56                                 result.append("&amp;");
  57                                 break;
  58
  59                         case '<':
  60                                 result.append("&lt;");
  61                                 break;
  62
  63                         case '>':
  64                                 result.append("&gt;");
  65                                 break;
  66
  67                         default:
  68                                    if (ch < 128)
  69                                    {
  70                                    result.append(ch);
  71                                }
  72                                    else
  73                                {
  74                                    result.append("&#").append((int)ch).append(";");
  75                                }
  76                         }
  77                 }
  78
  79                 return result.toString();
  80         }
  81 }