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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.archiver;
20  
21  import java.util.Arrays;
22  import java.util.Map;
23  
24  import org.apache.maven.model.Plugin;
25  import org.apache.maven.model.PluginContainer;
26  import org.apache.maven.project.MavenProject;
27  import org.codehaus.plexus.util.xml.Xpp3Dom;
28  
29  /**
30   * Helper to detect info about build info in a MavenProject, as configured in plugins.
31   *
32   * @since 3.6.5
33   */
34  public class BuildHelper {
35      /**
36       * Tries to determine the target Java release from the following sources (until one is found)
37       * <ol>
38       * <li>use {@code release} configuration of {@code org.apache.maven.plugins:maven-compiler-plugin}</li>
39       * <li>use {@code maven.compiler.release<} property</li>
40       * <li>use {@code target} configuration of {@code org.apache.maven.plugins:maven-compiler-plugin}</li>
41       * <li>use {@code maven.compiler.target} property</li>
42       * </ol>
43       *
44       * @param project not null
45       * @return the Java release version configured in the project, or null if not configured
46       */
47      public static String discoverJavaRelease(MavenProject project) {
48          Plugin compiler = getCompilerPlugin(project);
49  
50          String jdk = getPluginParameter(project, compiler, "release", "maven.compiler.release");
51  
52          if (jdk == null) {
53              jdk = getPluginParameter(project, compiler, "target", "maven.compiler.target");
54          }
55  
56          return normalizeJavaVersion(jdk);
57      }
58  
59      /**
60       * Normalize Java version, for versions 5 to 8 where there is a 1.x alias.
61       *
62       * @param jdk can be null
63       * @return normalized version if an alias was used
64       */
65      public static String normalizeJavaVersion(String jdk) {
66          if (jdk != null
67                  && jdk.length() == 3
68                  && Arrays.asList("1.5", "1.6", "1.7", "1.8").contains(jdk)) {
69              jdk = jdk.substring(2);
70          }
71          return jdk;
72      }
73  
74      public static Plugin getCompilerPlugin(MavenProject project) {
75          return getPlugin(project, "org.apache.maven.plugins:maven-compiler-plugin");
76      }
77  
78      /**
79       * Get plugin from project based on coordinates {@code groupId:artifactId}.
80       *
81       * @param project not null
82       * @param pluginGa {@code groupId:artifactId}
83       * @return the plugin from build or pluginManagement, if available in project
84       */
85      public static Plugin getPlugin(MavenProject project, String pluginGa) {
86          Plugin plugin = getPlugin(project.getBuild(), pluginGa);
87          if (plugin == null) {
88              plugin = getPlugin(project.getPluginManagement(), pluginGa);
89          }
90          return plugin;
91      }
92  
93      /**
94       * Get plugin parameter value if configured in current project.
95       *
96       * @param project not null
97       * @param plugin can be null
98       * @param parameter the parameter name when configured in plugin's configuration
99       * @param defaultValueProperty the property name when default value is used for the plugin parameter
100      * @return the value, or null if not configured at all, but using internal default from plugin.
101      */
102     public static String getPluginParameter(
103             MavenProject project, Plugin plugin, String parameter, String defaultValueProperty) {
104         String value = getPluginParameter(plugin, parameter);
105         if (value == null) {
106             value = project.getProperties().getProperty(defaultValueProperty);
107         }
108         return value;
109     }
110 
111     private static Plugin getPlugin(PluginContainer container, String pluginGa) {
112         if (container == null) {
113             return null;
114         }
115         Map<String, Plugin> pluginsAsMap = container.getPluginsAsMap();
116         return pluginsAsMap.get(pluginGa);
117     }
118 
119     private static String getPluginParameter(Plugin plugin, String parameter) {
120         if (plugin != null) {
121             Xpp3Dom pluginConf = (Xpp3Dom) plugin.getConfiguration();
122 
123             if (pluginConf != null) {
124                 Xpp3Dom target = pluginConf.getChild(parameter);
125 
126                 if (target != null) {
127                     return target.getValue();
128                 }
129             }
130         }
131         return null;
132     }
133 }