* the {@code JvmPluginExtension} extension.  It is used to configure many of the project's
 * JVM-related settings and behavior.
 *
 * @since 4.10
 */
public interface JavaPluginExtension {

    /**
     * Returns the source compatibility used for compiling Java sources.
     */
    JavaVersion getSourceCompatibility();

    /**

        DefaultJavaPluginExtension javaPluginExtension = addExtensions(project);

        configureCompileDefaults(project, javaPluginExtension);
        configureSourceSetDefaults(project, javaPluginExtension);
        configureJavaDoc(project, javaPluginExtension);

        configureTest(project, javaPluginExtension);
        configureBuildNeeded(project);

            run.getJvmArguments().convention(project.provider(pluginExtension::getApplicationDefaultJvmArgs));

            JavaPluginExtension javaPluginExtension = project.getExtensions().getByType(JavaPluginExtension.class);
            run.getModularity().getInferModulePath().convention(javaPluginExtension.getModularity().getInferModulePath());
            ObjectFactory objectFactory = project.getObjects();

        final JavaPluginExtension extension = javaPluginExtension(project);
        final JavaToolchainService service = extensionOf(project, JavaToolchainService.class);
        return service.launcherFor(extension.getToolchain());
    }

    private static JavaPluginExtension javaPluginExtension(Project project) {
        return extensionOf(project, JavaPluginExtension.class);
    }

                javadoc.setSource(sourceSet.getAllJava());
                if (javaPluginExtension != null) {
                    javadoc.getConventionMapping().map("destinationDir", () -> javaPluginExtension.getDocsDir().dir(javadocTaskName).get().getAsFile());
                    javadoc.getModularity().getInferModulePath().convention(javaPluginExtension.getModularity().getInferModulePath());
                }
            });
        }

        final JavaPluginExtension extension = javaPluginExtension(project);
        final JavaToolchainService service = extensionOf(project, JavaToolchainService.class);
        return service.launcherFor(extension.getToolchain());
    }

    private static JavaPluginExtension javaPluginExtension(Project project) {
        return extensionOf(project, JavaPluginExtension.class);
    }

                        for (SourceSet sourceSet : project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets()) {
                            task.dependsOn(sourceSet.getOutput().getDirs());
                        }
                    }
                });

                SourceSetContainer sourceSets = project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets();

            return p.getExtensions().getByType(JavaPluginExtension.class).getSourceCompatibility();
        }
    };
    public static final Function<Project, JavaVersion> TARGET_COMPATIBILITY = new Function<Project, JavaVersion>() {
        @Override
        public JavaVersion apply(Project p) {
            return p.getExtensions().getByType(JavaPluginExtension.class).getTargetCompatibility();
        }
    };

        if (extendProductionCode) {
            doExtendProductionCode();
        }

        JavaPluginExtension javaPluginExtension = project.getExtensions().findByType(JavaPluginExtension.class);
        JvmPluginsHelper.configureJavaDocTask("'" + name + "' feature", sourceSet, tasks, javaPluginExtension);
    }

    void doExtendProductionCode() {

import org.gradle.api.artifacts.Configuration;
import org.gradle.api.internal.ConventionMapping;
import org.gradle.api.internal.IConventionAware;
import org.gradle.api.plugins.JavaPlugin;
import org.gradle.api.plugins.JavaPluginExtension;
import org.gradle.api.plugins.WarPlugin;
import org.gradle.api.plugins.internal.JavaPluginHelper;
import org.gradle.api.tasks.TaskProvider;
import org.gradle.api.tasks.bundling.War;