1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.maven.cli.logging;
20
21 import java.io.IOException;
22 import java.io.InputStream;
23 import java.net.URL;
24 import java.util.Enumeration;
25 import java.util.Properties;
26
27 import org.apache.maven.cli.logging.impl.UnsupportedSlf4jBindingConfiguration;
28 import org.slf4j.ILoggerFactory;
29
30 /**
31 * Slf4jConfiguration factory, loading implementations from <code>META-INF/maven/slf4j-configuration.properties</code>
32 * configuration files in class loader: key is the class name of the ILoggerFactory, value is the class name of
33 * the corresponding Slf4jConfiguration.
34 *
35 * @since 3.1.0
36 */
37 public class Slf4jConfigurationFactory {
38 public static final String RESOURCE = "META-INF/maven/slf4j-configuration.properties";
39
40 public static Slf4jConfiguration getConfiguration(ILoggerFactory loggerFactory) {
41 String slf4jBinding = loggerFactory.getClass().getCanonicalName();
42
43 try {
44 Enumeration<URL> resources =
45 Slf4jConfigurationFactory.class.getClassLoader().getResources(RESOURCE);
46
47 while (resources.hasMoreElements()) {
48 URL resource = resources.nextElement();
49 try {
50 InputStream is = resource.openStream();
51 final Properties properties = new Properties();
52 if (is != null) {
53 try (InputStream in = is) {
54 properties.load(in);
55 }
56 }
57 String impl = properties.getProperty(slf4jBinding);
58 if (impl != null) {
59 return (Slf4jConfiguration) Class.forName(impl).newInstance();
60 }
61 } catch (IOException | ClassNotFoundException | IllegalAccessException | InstantiationException ex) {
62 // ignore and move on to the next
63 }
64 }
65 } catch (IOException ex) {
66 // ignore
67 }
68
69 return new UnsupportedSlf4jBindingConfiguration();
70 }
71 }