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
18 package org.apache.any23.source;
19
20 import java.io.IOException;
21 import java.io.InputStream;
22
23 /**
24 * A source of input streams. Mostly intended for situations where opening of an input stream is to be delayed.
25 *
26 * @author Richard Cyganiak (richard@cyganiak.de)
27 */
28 public interface DocumentSource {
29
30 /**
31 * Returns the input stream for accessing the content of the document.
32 *
33 * @return not <code>null</code> input stream for accessing document data.
34 *
35 * @throws IOException
36 * if there is an error opening the {@link org.apache.any23.source.DocumentSource}
37 * {@link java.io.InputStream}
38 */
39 InputStream openInputStream() throws IOException;
40
41 /**
42 * @return a string describing the content type of the provided document.
43 */
44 public String getContentType();
45
46 /**
47 * @return the size of the content length in bytes.
48 */
49 public long getContentLength();
50
51 /**
52 * @return the actual, final, canonical IRI if redirects occur.
53 */
54 public String getDocumentIRI();
55
56 /**
57 * A value of <i>false</i> indicates that the document resides remotely, and that multiple successive accesses to it
58 * should be avoided by copying it to local storage. This can also be used for sources that do not support multiple
59 * calls to {@link #openInputStream()}.
60 *
61 * @return true if the {@link org.apache.any23.source.DocumentSource} is cached locally.
62 */
63 public boolean isLocal();
64 }