View Javadoc

1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  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  package org.apache.tika.sax;
18  
19  import org.apache.tika.io.ClosedInputStream;
20  import org.xml.sax.ContentHandler;
21  import org.xml.sax.InputSource;
22  
23  /**
24   * Content handler decorator that always returns an empty stream from the
25   * {@link #resolveEntity(String, String)} method to prevent potential
26   * network or other external resources from being accessed by an XML parser.
27   *
28   * @see <a href="https://issues.apache.org/jira/browse/TIKA-185">TIKA-185</a>
29   */
30  public class OfflineContentHandler extends ContentHandlerDecorator {
31  
32      public OfflineContentHandler(ContentHandler handler) {
33          super(handler);
34      }
35  
36      /**
37       * Returns an empty stream. This will make an XML parser silently
38       * ignore any external entities.
39       */
40      @Override
41      public InputSource resolveEntity(String publicId, String systemId) {
42          return new InputSource(new ClosedInputStream());
43      }
44  
45  }