java9-modularity#72: initial refactorings/improvements

necessary for further commits

MAIN:
1) renamed TestModuleOptions.isRunOnClasspath() to getRunOnClasspath() (otherwise won't work with Kotlin DSL) + added a Kotlin DSL example for "runOnClasspath = true" to README.md
2) introduced JavaProjectHelper and applied it to CompileTask
3) added comments for all anonymous classes that should not be removed
4) minor improvements in ModuleSystemPlugin
5) minor fixes in test-project-kotlin/README.md

TEST:
1) bumped smoke-test Gradle version to 5.0 (for improved Kotlin DSL)
2) introduced a no-op "moduleOptions" access in greeter.api (for testing DSL)
3) introduced SmokeTestHelper for ModulePluginSmokeTest
4) disabled stackTraceFilters in all tests
5) updated Kotlin to 1.3.20

README.md

@@ -265,7 +265,10 @@ See `src/test/java/module-info.test` and `src/test/java/greeter/ScriptingTest.ja
 Fall-back to classpath mode
 ----
 
-If for whatever reason this is unwanted or introduces problems, you can enable classpath mode, which essentially turns of the plugin while running tests.
+If for whatever reason this is unwanted or introduces problems, you can enable classpath mode, which essentially turns off the plugin while running tests.
+
+<details open>
+<summary>Groovy DSL</summary>
 
 ```groovy
 test {
@@ -275,6 +278,22 @@ test {
 }
 ```
 
+</details>
+<details>
+<summary>Kotlin DSL</summary>
+
+```kotlin
+tasks {
+    test {
+        extensions.configure(TestModuleOptions::class) {
+            runOnClasspath = true
+        }
+    }
+}
+```
+
+</details>
+
 Blackbox testing
 ===
 
@@ -286,7 +305,7 @@ This module `requires` and/or `uses` the module under test, and tests it's exter
 In the following example we test a module `greeter.provider`, which provides a service implementation of type `Greeter`.
 The `Greeter` type is provided by yet another module `greeter.api`.
 
-The test module would typically be named something similar to the the module it's testing, e.g. `greeter.provider.test`.
+The test module would typically be named something similar to the module it's testing, e.g. `greeter.provider.test`.
 In `src/main/java` it has some code that looks like code that you would normally write to use the module that's being tested.
 For example, we do a service lookup.
 

build.gradle

@@ -58,6 +58,7 @@ test {
 
     testLogging {
         events 'PASSED', 'FAILED', 'SKIPPED'
+        stackTraceFilters = []
     }
 }
 

src/main/java/org/javamodularity/moduleplugin/JavaProjectHelper.java

@@ -0,0 +1,63 @@
+package org.javamodularity.moduleplugin;
+
+import org.gradle.api.Project;
+import org.gradle.api.Task;
+import org.gradle.api.plugins.JavaPlugin;
+import org.gradle.api.tasks.SourceSet;
+import org.gradle.api.tasks.SourceSetContainer;
+import org.gradle.api.tasks.compile.JavaCompile;
+
+import java.util.Optional;
+
+/**
+ * Generic helper for Gradle {@link Project} API that has {@link JavaPlugin} applied.
+ */
+public final class JavaProjectHelper {
+
+    private final Project project;
+
+    public JavaProjectHelper(Project project) {
+        this.project = project;
+    }
+
+    public Project project() {
+        return project;
+    }
+
+    //region SOURCE SETS
+    public SourceSetContainer sourceSets() {
+        return project.getExtensions().getByType(SourceSetContainer.class);
+    }
+
+    public SourceSet sourceSet(String sourceSetName) {
+        return sourceSets().getByName(sourceSetName);
+    }
+
+    public SourceSet mainSourceSet() {
+        return sourceSet(SourceSet.MAIN_SOURCE_SET_NAME);
+    }
+
+    public SourceSet testSourceSet(String sourceSetName) {
+        return sourceSet(SourceSet.TEST_SOURCE_SET_NAME);
+    }
+    //endregion
+
+    //region TASKS
+    public Task task(String taskName) {
+        return project.getTasks().getByName(taskName);
+    }
+
+    public JavaCompile compileJavaTask(String taskName) {
+        return (JavaCompile) task(taskName);
+    }
+
+    public Optional<Task> findTask(String taskName) {
+        return Optional.ofNullable(project.getTasks().findByName(taskName));
+    }
+
+    public Optional<JavaCompile> findCompileJavaTask(String taskName) {
+        return findTask(taskName).map(JavaCompile.class::cast);
+    }
+    //endregion
+
+}

src/main/java/org/javamodularity/moduleplugin/ModuleSystemPlugin.java

@@ -2,28 +2,29 @@
 
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
+import org.gradle.api.plugins.ExtensionContainer;
 import org.gradle.api.plugins.JavaPlugin;
 import org.javamodularity.moduleplugin.tasks.*;
 
-import java.util.Optional;
-
 public class ModuleSystemPlugin implements Plugin<Project> {
 
     @Override
     public void apply(Project project) {
         project.getPlugins().apply(JavaPlugin.class);
-        Optional<String> foundModuleName = new ModuleName().findModuleName(project);
-        foundModuleName.ifPresent(moduleName -> {
-            project.getExtensions().add("moduleName", moduleName);
-            project.getExtensions().create("patchModules", PatchModuleExtension.class);
+        new ModuleName().findModuleName(project).ifPresent(moduleName -> configureModularity(project, moduleName));
+    }
+
+    private void configureModularity(Project project, String moduleName) {
+        ExtensionContainer extensions = project.getExtensions();
+        extensions.add("moduleName", moduleName);
+        extensions.create("patchModules", PatchModuleExtension.class);
 
-            new CompileTask().configureCompileJava(project);
-            new CompileTestTask().configureCompileTestJava(project, moduleName);
-            new TestTask().configureTestJava(project, moduleName);
-            new RunTask().configureRun(project, moduleName);
-            new JavadocTask().configureJavaDoc(project);
-            ModularJavaExec.configure(project, moduleName);
-            ModularCreateStartScripts.configure(project, moduleName);
-        });
+        new CompileTask(project).configureCompileJava();
+        new CompileTestTask().configureCompileTestJava(project, moduleName);
+        new TestTask().configureTestJava(project, moduleName);
+        new RunTask().configureRun(project, moduleName);
+        new JavadocTask().configureJavaDoc(project);
+        ModularJavaExec.configure(project, moduleName);
+        ModularCreateStartScripts.configure(project, moduleName);
     }
 }

src/main/java/org/javamodularity/moduleplugin/tasks/CompileJavaTaskMutator.java

@@ -9,6 +9,8 @@
 
 class CompileJavaTaskMutator {
 
+    private static final String COMPILE_KOTLIN_TASK_NAME = "compileKotlin";
+
     static void mutateJavaCompileTask(Project project, JavaCompile compileJava) {
         ModuleOptions moduleOptions = compileJava.getExtensions().getByType(ModuleOptions.class);
         PatchModuleExtension patchModuleExtension = project.getExtensions().getByType(PatchModuleExtension.class);
@@ -26,7 +28,8 @@ static void mutateJavaCompileTask(Project project, JavaCompile compileJava) {
         compileJava.getOptions().setCompilerArgs(compilerArgs);
         compileJava.setClasspath(project.files());
 
-        AbstractCompile compileKotlin = (AbstractCompile) project.getTasks().findByName("compileKotlin");
+        // https://github.com/java9-modularity/gradle-modules-plugin/issues/45
+        AbstractCompile compileKotlin = (AbstractCompile) project.getTasks().findByName(COMPILE_KOTLIN_TASK_NAME);
         if (compileKotlin != null) {
             compileJava.setDestinationDir(compileKotlin.getDestinationDir());
         }

src/main/java/org/javamodularity/moduleplugin/tasks/CompileTask.java

@@ -5,26 +5,34 @@
 import org.gradle.api.Task;
 import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.tasks.compile.JavaCompile;
+import org.javamodularity.moduleplugin.JavaProjectHelper;
 
 public class CompileTask {
 
-    public void configureCompileJava(Project project) {
-        JavaCompile compileJava = (JavaCompile) project.getTasks().findByName(JavaPlugin.COMPILE_JAVA_TASK_NAME);
-        if (compileJava != null) {
-            compileJava.getExtensions().create("moduleOptions", ModuleOptions.class, project);
+    private final Project project;
 
-            compileJava.doFirst(new Action<Task>() {
+    public CompileTask(Project project) {
+        this.project = project;
+    }
+
+    public void configureCompileJava() {
+        helper().findCompileJavaTask(JavaPlugin.COMPILE_JAVA_TASK_NAME)
+                .ifPresent(this::configureCompileJava);
+    }
 
-                /* (non-Javadoc)
-                 * @see org.gradle.api.Action#execute(java.lang.Object)
-                 */
-                @Override
-                public void execute(Task task) {
-                    CompileJavaTaskMutator.mutateJavaCompileTask(project, compileJava);
-                }
+    private void configureCompileJava(JavaCompile compileJava) {
+        compileJava.getExtensions().create("moduleOptions", ModuleOptions.class, project);
 
-            });
-        }
+        // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
+        compileJava.doFirst(new Action<Task>() {
+            @Override
+            public void execute(Task task) {
+                CompileJavaTaskMutator.mutateJavaCompileTask(project, compileJava);
+            }
+        });
     }
 
+    private JavaProjectHelper helper() {
+        return new JavaProjectHelper(project);
+    }
 }

src/main/java/org/javamodularity/moduleplugin/tasks/CompileTestTask.java

@@ -1,9 +1,5 @@
 package org.javamodularity.moduleplugin.tasks;
 
-import java.util.ArrayList;
-import java.util.List;
-import java.util.function.Consumer;
-
 import org.gradle.api.Action;
 import org.gradle.api.Project;
 import org.gradle.api.Task;
@@ -13,6 +9,9 @@
 import org.gradle.api.tasks.compile.JavaCompile;
 import org.javamodularity.moduleplugin.TestEngine;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class CompileTestTask {
 
     public void configureCompileTestJava(Project project, String moduleName) {
@@ -23,11 +22,8 @@ public void configureCompileTestJava(Project project, String moduleName) {
         compileTestJava.getExtensions().create("moduleOptions", ModuleOptions.class, project);
         SourceSet testSourceSet = javaConvention.getSourceSets().getByName(SourceSet.TEST_SOURCE_SET_NAME);
 
+        // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
         compileTestJava.doFirst(new Action<Task>() {
-
-            /* (non-Javadoc)
-             * @see org.gradle.api.Action#execute(java.lang.Object)
-             */
             @Override
             public void execute(Task task) {
                 var args = new ArrayList<>(compileTestJava.getOptions().getCompilerArgs());
@@ -38,19 +34,10 @@ public void execute(Task task) {
                         "--patch-module", moduleName + "=" + testSourceSet.getJava().getSourceDirectories().getAsPath()
                 ));
 
-                TestEngine.select(project).ifPresent(new Consumer<TestEngine>() {
-
-                    /* (non-Javadoc)
-                     * @see java.util.function.Consumer#accept(java.lang.Object)
-                     */
-                    @Override
-                    public void accept(TestEngine testEngine) {
-                        args.addAll(List.of(
-                                "--add-modules", testEngine.moduleName,
-                                "--add-reads", moduleName + "=" + testEngine.moduleName));
-                    }
-
-                });
+                TestEngine.select(project).ifPresent(testEngine -> args.addAll(List.of(
+                        "--add-modules", testEngine.moduleName,
+                        "--add-reads", moduleName + "=" + testEngine.moduleName
+                )));
 
                 ModuleOptions moduleOptions = compileTestJava.getExtensions().getByType(ModuleOptions.class);
                 moduleOptions.mutateArgs(moduleName, args);

src/main/java/org/javamodularity/moduleplugin/tasks/JavadocTask.java

@@ -4,7 +4,6 @@
 import org.gradle.api.Project;
 import org.gradle.api.Task;
 import org.gradle.api.plugins.JavaPlugin;
-import org.gradle.api.tasks.compile.JavaCompile;
 import org.gradle.api.tasks.javadoc.Javadoc;
 import org.gradle.external.javadoc.CoreJavadocOptions;
 
@@ -16,11 +15,8 @@ public void configureJavaDoc(Project project) {
             javadoc.getExtensions().create("moduleOptions", ModuleOptions.class, project);
             PatchModuleExtension patchModuleExtension = project.getExtensions().getByType(PatchModuleExtension.class);
 
+            // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
             javadoc.doFirst(new Action<Task>() {
-
-                /* (non-Javadoc)
-                 * @see org.gradle.api.Action#execute(java.lang.Object)
-                 */
                 @Override
                 public void execute(Task task) {
                     ModuleOptions moduleOptions = javadoc.getExtensions().getByType(ModuleOptions.class);

src/main/java/org/javamodularity/moduleplugin/tasks/RunTaskMutator.java

@@ -6,8 +6,7 @@
 import org.gradle.api.Task;
 import org.gradle.api.distribution.Distribution;
 import org.gradle.api.distribution.DistributionContainer;
-import org.gradle.api.file.CopySpec;
-import org.gradle.api.file.FileCollection;
+import org.gradle.api.file.RelativePath;
 import org.gradle.api.logging.Logger;
 import org.gradle.api.logging.Logging;
 import org.gradle.api.plugins.JavaPluginConvention;
@@ -21,7 +20,6 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 public class RunTaskMutator {
@@ -54,6 +52,7 @@ public void updateStartScriptsTask(String taskStartScriptsName) {
     public void updateStartScriptsTask(CreateStartScripts startScriptsTask) {
         PatchModuleExtension patchModuleExtension = project.getExtensions().getByType(PatchModuleExtension.class);
 
+        // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
         startScriptsTask.doFirst(new Action<Task>() {
             @Override
             public void execute(final Task task) {
@@ -86,6 +85,7 @@ public void execute(final Task task) {
             }
         });
 
+        // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
         startScriptsTask.doLast(new Action<Task>() {
             @Override
             public void execute(final Task task) {
@@ -100,20 +100,18 @@ public void execute(final Task task) {
     public void movePatchedLibs() {
         PatchModuleExtension patchModuleExtension = project.getExtensions().getByType(PatchModuleExtension.class);
 
-        if(!patchModuleExtension.getConfig().isEmpty()) {
+        if (!patchModuleExtension.getConfig().isEmpty()) {
             Distribution distribution = ((DistributionContainer) project.getExtensions().getByName("distributions")).getByName("main");
-            distribution.contents(new Action<CopySpec>() {
-                @Override
-                public void execute(CopySpec copySpec) {
-                    copySpec.filesMatching(patchModuleExtension.getJars(), (action) -> {
-                        action.setRelativePath(action.getRelativePath().getParent().getParent().append(true, "patchlibs", action.getName()));
-                    });
-                }
-            });
+            distribution.contents(copySpec -> copySpec.filesMatching(patchModuleExtension.getJars(), action -> {
+                RelativePath relativePath = action.getRelativePath().getParent().getParent()
+                        .append(true, "patchlibs", action.getName());
+                action.setRelativePath(relativePath);
+            }));
         }
     }
 
     private void updateJavaExecTask() {
+        // don't convert to lambda: https://github.com/java9-modularity/gradle-modules-plugin/issues/54
         execTask.doFirst(new Action<Task>() {
             @Override
             public void execute(final Task task) {

src/main/java/org/javamodularity/moduleplugin/tasks/TestModuleOptions.java

@@ -10,7 +10,7 @@ public TestModuleOptions(Project project) {
         super(project);
     }
 
-    public boolean isRunOnClasspath() {
+    public boolean getRunOnClasspath() {
         return runOnClasspath;
     }