1 /*
2 * Copyright 2021 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16
17 package io.netty.handler.codec.compression;
18
19 import com.aayushatharva.brotli4j.Brotli4jLoader;
20 import io.netty.util.internal.PlatformDependent;
21 import io.netty.util.internal.logging.InternalLogger;
22 import io.netty.util.internal.logging.InternalLoggerFactory;
23
24 public final class Brotli {
25
26 private static final InternalLogger logger = InternalLoggerFactory.getInstance(Brotli.class);
27 private static final ClassNotFoundException CNFE;
28 private static Throwable cause;
29
30 static {
31 ClassNotFoundException cnfe = null;
32
33 try {
34 Class.forName("com.aayushatharva.brotli4j.Brotli4jLoader", false,
35 PlatformDependent.getClassLoader(Brotli.class));
36 } catch (ClassNotFoundException t) {
37 cnfe = t;
38 logger.debug(
39 "brotli4j not in the classpath; Brotli support will be unavailable.");
40 }
41
42 CNFE = cnfe;
43
44 // If in the classpath, try to load the native library and initialize brotli4j.
45 if (cnfe == null) {
46 cause = Brotli4jLoader.getUnavailabilityCause();
47 if (cause != null) {
48 logger.debug("Failed to load brotli4j; Brotli support will be unavailable.", cause);
49 }
50 }
51 }
52
53 /**
54 *
55 * @return true when brotli4j is in the classpath
56 * and native library is available on this platform and could be loaded
57 */
58 public static boolean isAvailable() {
59 return CNFE == null && Brotli4jLoader.isAvailable();
60 }
61
62 /**
63 * Throws when brotli support is missing from the classpath or is unavailable on this platform
64 * @throws Throwable a ClassNotFoundException if brotli4j is missing
65 * or a UnsatisfiedLinkError if brotli4j native lib can't be loaded
66 */
67 public static void ensureAvailability() throws Throwable {
68 if (CNFE != null) {
69 throw CNFE;
70 }
71 Brotli4jLoader.ensureAvailability();
72 }
73
74 /**
75 * Returns {@link Throwable} of unavailability cause
76 */
77 public static Throwable cause() {
78 return cause;
79 }
80
81 private Brotli() {
82 }
83 }