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.zip.GZIPInputStream;
20
21 /** Filter for gzip compressed data.
22 * @author Luc Maisonobe
23 * @since 9.2
24 */
25 public class GzipFilter implements DataFilter {
26
27 /** Suffix for gzip compressed files. */
28 private static final String SUFFIX = ".gz";
29
30 /** Empty constructor.
31 * <p>
32 * This constructor is not strictly necessary, but it prevents spurious
33 * javadoc warnings with JDK 18 and later.
34 * </p>
35 * @since 12.0
36 */
37 public GzipFilter() {
38 // nothing to do
39 }
40
41 /** {@inheritDoc} */
42 @Override
43 public DataSource filter(final DataSource original) {
44 final String oName = original.getName();
45 final DataSource.Opener oOpener = original.getOpener();
46 if (oName.endsWith(SUFFIX)) {
47 final String fName = oName.substring(0, oName.length() - SUFFIX.length());
48 final DataSource.StreamOpener fOpener = () -> new GZIPInputStream(oOpener.openStreamOnce());
49 return new DataSource(fName, fOpener);
50 } else {
51 return original;
52 }
53 }
54
55 }