1   /* Copyright 2002-2025 CS GROUP
2    * Licensed to CS GROUP (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS 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.orekit.data;
18  
19  import java.util.regex.Pattern;
20  
21  /** Interface for providing data files to {@link DataLoader file loaders}.
22   * <p>
23   * This interface defines a generic way to explore some collection holding
24   * data files and load some of them. The collection may be a list of resources
25   * in the classpath, a directories tree in filesystem, a zip or jar archive,
26   * a database, a connexion to a remote server ...
27   * </p>
28   * <p>
29   * The proper way to use this interface is to configure one or more
30   * implementations and register them in the {@link DataProvidersManager data
31   * providers manager singleton}, or to let this manager use its default
32   * configuration. Once registered, they will be used automatically whenever
33   * some data needs to be loaded. This allow high level applications developers
34   * to customize Orekit data loading mechanism and get a tighter integration of
35   * the library within their application.
36   * </p>
37   * @see DataLoader
38   * @see DataProvidersManager
39   * @author Luc Maisonobe
40   */
41  public interface DataProvider {
42  
43      /** Pattern for name of zip/jar archives. */
44      Pattern ZIP_ARCHIVE_PATTERN = Pattern.compile("(.*)(?:(?:\\.zip)|(?:\\.jar))$");
45  
46      /** Feed a data file loader by browsing the data collection.
47       * <p>
48       * The method crawls all files referenced in the instance (for example
49       * all files in a directories tree) and for each file supported by the
50       * file loader it asks the file loader to load it.
51       * </p>
52       * <p>
53       * If the method completes without exception, then the data loader
54       * is considered to have been fed successfully and the top level
55       * {@link DataProvidersManager data providers manager} will return
56       * immediately without attempting to use the next configured providers.
57       * </p>
58       * <p>
59       * If the method completes abruptly with an exception, then the top level
60       * {@link DataProvidersManager data providers manager} will try to use
61       * the next configured providers, in case another one can feed the
62       * {@link DataLoader data loader}.
63       * </p>
64       *
65       * @param supported pattern for file names supported by the visitor
66       * @param visitor data file visitor to use
67       * @param manager with the filters to apply to the resources.
68       * @return true if some data has been loaded
69       */
70      boolean feed(Pattern supported, DataLoader visitor, DataProvidersManager manager);
71  
72  }