[tycho-4.0.x] Improve PluginConfigurationHelper by using a dedicated object

tycho-packaging-plugin/src/main/java/org/eclipse/tycho/packaging/BndManifestProcessor.java

@@ -75,8 +75,8 @@ public BndManifestProcessor(MavenSession mavenSession) {
 	@Override
 	public void processManifest(MavenProject mavenProject, Manifest manifest) {
 
-		if (configurationHelper.getBooleanOption("deriveHeaderFromSource")
-				// don't be confused here, we use FALSE als default because it means no such
+		if (configurationHelper.getConfiguration().getBoolean("deriveHeaderFromSource")
+				// don't be confused here, we use FALSE as default because it means no such
 				// configuration option defined in the mojo (probably called from different
 				// context) but the default in the PackagePluginMojo defines the real default
 				// (what is TRUE)

tycho-spi/src/main/java/org/eclipse/tycho/helper/PluginConfigurationHelper.java

@@ -12,10 +12,23 @@
  *******************************************************************************/
 package org.eclipse.tycho.helper;
 
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
 
+import org.apache.maven.plugin.LegacySupport;
+import org.apache.maven.plugin.Mojo;
 import org.apache.maven.plugin.MojoExecution;
+import org.apache.maven.plugin.descriptor.MojoDescriptor;
+import org.apache.maven.plugin.descriptor.PluginDescriptor;
+import org.apache.maven.plugin.descriptor.PluginDescriptorBuilder;
 import org.codehaus.plexus.component.annotations.Component;
+import org.codehaus.plexus.component.annotations.Requirement;
+import org.codehaus.plexus.util.InterpolationFilterReader;
 import org.codehaus.plexus.util.xml.Xpp3Dom;
 
 /**
@@ -24,26 +37,101 @@
 @Component(role = PluginConfigurationHelper.class)
 public class PluginConfigurationHelper {
 
-    public Optional<Xpp3Dom> getDomOption(String name) {
-        Optional<MojoExecution> execution = MojoExecutionHelper.getExecution();
-        Optional<Xpp3Dom> configuration = execution.map(ex -> ex.getConfiguration());
-        Optional<Xpp3Dom> child = configuration.map(cfg -> cfg.getChild(name));
-        return child;
+    @Requirement
+    ProjectHelper projectHelper;
+
+    @Requirement
+    LegacySupport legacySupport;
+
+    private Map<URL, PluginDescriptor> descriptorCache = new ConcurrentHashMap<>();
+
+    public Configuration getConfiguration() {
+        MojoExecution execution = MojoExecutionHelper.getExecution().orElse(null);
+        if (execution == null) {
+            return new Configuration(null);
+        }
+        Xpp3Dom configuration = execution.getConfiguration();
+        return getConfiguration(configuration);
+    }
+
+    public Configuration getConfiguration(Xpp3Dom configuration) {
+        return new Configuration(configuration);
     }
 
-    public Optional<String> getStringOption(String name) {
-        return getDomOption(name).map(child -> {
-            String value = child.getValue();
-            if (value == null) {
-                String attribute = child.getAttribute("default-value");
-                return attribute;
+    public <M extends Mojo> Configuration getConfiguration(Class<M> mojo) {
+        URL resource = mojo.getResource("/META-INF/maven/plugin.xml");
+        if (resource == null) {
+            throw new IllegalStateException("can't find plugin descriptor of mojo " + mojo.getName());
+        }
+        PluginDescriptor pluginDescriptor = descriptorCache.computeIfAbsent(resource, url -> {
+            try (BufferedReader reader = new BufferedReader(new InputStreamReader(resource.openStream()))) {
+                InterpolationFilterReader interpolationFilterReader = new InterpolationFilterReader(reader, Map.of());
+                return new PluginDescriptorBuilder().build(interpolationFilterReader);
+            } catch (Exception e) {
             }
-            return value;
+            return null;
         });
+        if (pluginDescriptor == null) {
+            throw new IllegalStateException("can't load plugin descriptor of mojo " + mojo.getName());
+        }
+        for (MojoDescriptor mojoDescriptor : pluginDescriptor.getMojos()) {
+            if (mojo.getName().equals(mojoDescriptor.getImplementation())) {
+                Xpp3Dom configuration = projectHelper.getPluginConfiguration(pluginDescriptor.getGroupId(),
+                        pluginDescriptor.getArtifactId(), mojoDescriptor.getGoal());
+                return getConfiguration(configuration);
+
+            }
+        }
+        throw new IllegalArgumentException("can't find mojo " + mojo.getName()
+                + " goal in descriptor, possible goals are "
+                + pluginDescriptor.getMojos().stream().map(MojoDescriptor::getGoal).collect(Collectors.joining(",")));
     }
 
-    public Optional<Boolean> getBooleanOption(String name) {
-        return getStringOption(name).map(s -> Boolean.valueOf(s));
+    public static final class Configuration {
+
+        private Xpp3Dom configuration;
+
+        Configuration(Xpp3Dom configuration) {
+            this.configuration = configuration;
+        }
+
+        public Optional<Configuration> getChild(String name) {
+            if (configuration == null) {
+                return Optional.empty();
+            }
+            Xpp3Dom child = configuration.getChild(name);
+            if (child == null) {
+                return Optional.empty();
+            }
+            return Optional.of(new Configuration(child));
+        }
+
+        public Optional<String> getString(String name) {
+            return getChild(name).map(child -> {
+                String value = child.configuration.getValue();
+                if (value == null) {
+                    return child.configuration.getAttribute("default-value");
+                }
+                return value;
+            });
+        }
+
+        public Optional<Boolean> getBoolean(String name) {
+            return getString(name).map(Boolean::valueOf);
+        }
+
+        public <E extends Enum<E>> Optional<E> getEnum(String name, Class<E> type) {
+            return getString(name).map(value -> {
+
+                for (E e : type.getEnumConstants()) {
+                    if (e.name().equals(value)) {
+                        return e;
+                    }
+                }
+                return null;
+            });
+        }
+
     }
 
 }

tycho-spi/src/main/java/org/eclipse/tycho/helper/ProjectHelper.java

@@ -12,6 +12,8 @@
  *******************************************************************************/
 package org.eclipse.tycho.helper;
 
+import java.io.IOException;
+import java.io.StringReader;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -21,19 +23,25 @@
 import org.apache.maven.lifecycle.internal.MojoDescriptorCreator;
 import org.apache.maven.model.Plugin;
 import org.apache.maven.model.PluginExecution;
+import org.apache.maven.plugin.LegacySupport;
 import org.apache.maven.plugin.descriptor.MojoDescriptor;
 import org.apache.maven.plugin.descriptor.PluginDescriptor;
 import org.apache.maven.project.MavenProject;
 import org.codehaus.plexus.component.annotations.Component;
 import org.codehaus.plexus.component.annotations.Requirement;
 import org.codehaus.plexus.util.xml.Xpp3Dom;
+import org.codehaus.plexus.util.xml.Xpp3DomBuilder;
+import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
 
 @Component(role = ProjectHelper.class)
 public class ProjectHelper {
 
     @Requirement
     private MojoDescriptorCreator mojoDescriptorCreator;
 
+    @Requirement
+    private LegacySupport legacySupport;
+
     private Map<String, Plugin> cliPlugins = new ConcurrentHashMap<String, Plugin>();
 
     /**
@@ -97,6 +105,18 @@ public boolean hasPluginExecution(String pluginGroupId, String pluginArtifactId,
         return false;
     }
 
+    public Xpp3Dom getPluginConfiguration(String pluginGroupId, String pluginArtifactId, String goal) {
+        MavenSession currentSession = legacySupport.getSession();
+        if (currentSession == null) {
+            return null;
+        }
+        MavenProject currentProject = currentSession.getCurrentProject();
+        if (currentProject == null) {
+            return null;
+        }
+        return getPluginConfiguration(pluginGroupId, pluginArtifactId, goal, currentProject, currentSession);
+    }
+
     public Xpp3Dom getPluginConfiguration(String pluginGroupId, String pluginArtifactId, String goal,
             MavenProject project, MavenSession mavenSession) {
         MavenSession clone = mavenSession.clone();
@@ -105,15 +125,39 @@ public Xpp3Dom getPluginConfiguration(String pluginGroupId, String pluginArtifac
         for (Plugin plugin : plugins) {
             if (plugin.getGroupId().equals(pluginGroupId) && plugin.getArtifactId().equals(pluginArtifactId)) {
                 if (goal == null) {
-                    return (Xpp3Dom) plugin.getConfiguration();
+                    return getDom(plugin.getConfiguration());
                 }
                 for (PluginExecution execution : plugin.getExecutions()) {
                     if (execution.getGoals().contains(goal)) {
-                        return (Xpp3Dom) execution.getConfiguration();
+                        return getDom(execution.getConfiguration());
                     }
                 }
             }
         }
         return null;
     }
+
+    public MavenProject getCurrentProject() {
+        MavenSession session = legacySupport.getSession();
+        if (session == null) {
+            return null;
+        }
+        return session.getCurrentProject();
+    }
+
+    public Xpp3Dom getDom(Object object) {
+        if (object == null) {
+            return null;
+        }
+        if (object instanceof Xpp3Dom xpp3) {
+            return xpp3;
+        }
+        try {
+            return Xpp3DomBuilder.build(new StringReader(object.toString()));
+        } catch (XmlPullParserException e) {
+            return null;
+        } catch (IOException e) {
+            return null;
+        }
+    }
 }