DataProvider.java
/* Copyright 2002-2022 CS GROUP
* Licensed to CS GROUP (CS) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* CS licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.orekit.data;
import java.util.regex.Pattern;
/** Interface for providing data files to {@link DataLoader file loaders}.
* <p>
* This interface defines a generic way to explore some collection holding
* data files and load some of them. The collection may be a list of resources
* in the classpath, a directories tree in filesystem, a zip or jar archive,
* a database, a connexion to a remote server ...
* </p>
* <p>
* The proper way to use this interface is to configure one or more
* implementations and register them in the {@link DataProvidersManager data
* providers manager singleton}, or to let this manager use its default
* configuration. Once registered, they will be used automatically whenever
* some data needs to be loaded. This allow high level applications developers
* to customize Orekit data loading mechanism and get a tighter integration of
* the library within their application.
* </p>
* @see DataLoader
* @see DataProvidersManager
* @author Luc Maisonobe
*/
public interface DataProvider {
/** Pattern for name of zip/jar archives. */
Pattern ZIP_ARCHIVE_PATTERN = Pattern.compile("(.*)(?:(?:\\.zip)|(?:\\.jar))$");
/** Feed a data file loader by browsing the data collection.
* <p>
* The method crawls all files referenced in the instance (for example
* all files in a directories tree) and for each file supported by the
* file loader it asks the file loader to load it.
* </p>
* <p>
* If the method completes without exception, then the data loader
* is considered to have been fed successfully and the top level
* {@link DataProvidersManager data providers manager} will return
* immediately without attempting to use the next configured providers.
* </p>
* <p>
* If the method completes abruptly with an exception, then the top level
* {@link DataProvidersManager data providers manager} will try to use
* the next configured providers, in case another one can feed the
* {@link DataLoader data loader}.
* </p>
*
* @param supported pattern for file names supported by the visitor
* @param visitor data file visitor to use
* @param manager with the filters to apply to the resources.
* @return true if some data has been loaded
*/
boolean feed(Pattern supported, DataLoader visitor, DataProvidersManager manager);
}