Remove configurability from Extension, move service loading

gradle-palantir-java-format/src/main/java/com/palantir/javaformat/gradle/FormatDiff.java

@@ -42,7 +42,7 @@
 import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
-public final class FormatDiff {
+final class FormatDiff {
     // each section in the git diff output starts like this
     private static final Pattern SEPARATOR = Pattern.compile("diff --git");
 

gradle-palantir-java-format/src/main/java/com/palantir/javaformat/gradle/JavaFormatExtension.java

@@ -16,20 +16,35 @@
 
 package com.palantir.javaformat.gradle;
 
+import com.google.common.collect.Iterables;
+import com.palantir.javaformat.java.FormatterService;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.ServiceLoader;
 import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.provider.Property;
 
 public class JavaFormatExtension {
-    private final Property<String> implementationVersion;
-    private static final String IMPLEMENTATION_VERSION =
-            JavaFormatExtension.class.getPackage().getImplementationVersion();
+    private final Configuration configuration;
 
-    public JavaFormatExtension(Project project) {
-        implementationVersion = project.getObjects().property(String.class);
-        implementationVersion.set(IMPLEMENTATION_VERSION);
+    public JavaFormatExtension(Configuration configuration) {
+        this.configuration = configuration;
     }
 
-    public final Property<String> getImplementationVersion() {
-        return implementationVersion;
+    public FormatterService serviceLoad() {
+        URL[] jarUris = configuration.getFiles().stream()
+                .map(file -> {
+                    try {
+                        return file.toURI().toURL();
+                    } catch (MalformedURLException e) {
+                        throw new RuntimeException("Unable to convert URI to URL: " + file, e);
+                    }
+                })
+                .toArray(URL[]::new);
+
+        ClassLoader classLoader = new URLClassLoader(jarUris, FormatterService.class.getClassLoader());
+        return Iterables.getOnlyElement(ServiceLoader.load(FormatterService.class, classLoader));
     }
 }

gradle-palantir-java-format/src/main/java/com/palantir/javaformat/gradle/PalantirJavaFormatPlugin.java

@@ -16,13 +16,8 @@
 
 package com.palantir.javaformat.gradle;
 
-import com.google.common.collect.Iterables;
 import com.palantir.javaformat.java.FormatterService;
 import java.io.IOException;
-import java.net.MalformedURLException;
-import java.net.URL;
-import java.net.URLClassLoader;
-import java.util.ServiceLoader;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
@@ -49,26 +44,10 @@ public FormatDiffTask() {
 
         @TaskAction
         public final void formatDiff() throws IOException, InterruptedException {
-            URL[] jarUris = getProject()
-                    .getRootProject()
-                    .getConfigurations()
-                    .getByName(PalantirJavaFormatProviderPlugin.CONFIGURATION_NAME)
-                    .getFiles()
-                    .stream()
-                    .map(file -> {
-                        try {
-                            return file.toURI().toURL();
-                        } catch (MalformedURLException e) {
-                            throw new RuntimeException("Unable to convert URI to URL: " + file, e);
-                        }
-                    })
-                    .toArray(URL[]::new);
-
-            ClassLoader classLoader = new URLClassLoader(jarUris, PalantirJavaFormatPlugin.class.getClassLoader());
-            FormatterService formatter =
-                    Iterables.getOnlyElement(ServiceLoader.load(FormatterService.class, classLoader));
-
-            FormatDiff.formatDiff(getProject().getProjectDir().toPath(), formatter);
+            JavaFormatExtension extension =
+                    getProject().getRootProject().getExtensions().getByType(JavaFormatExtension.class);
+            FormatterService formatterService = extension.serviceLoad();
+            FormatDiff.formatDiff(getProject().getProjectDir().toPath(), formatterService);
         }
     }
 }

gradle-palantir-java-format/src/main/java/com/palantir/javaformat/gradle/PalantirJavaFormatProviderPlugin.java

@@ -20,34 +20,31 @@
 import com.google.common.collect.ImmutableMap;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
 
 public final class PalantirJavaFormatProviderPlugin implements Plugin<Project> {
 
-    public static final String CONFIGURATION_NAME = "palantirJavaFormat";
+    static final String CONFIGURATION_NAME = "palantirJavaFormat";
 
     @Override
-    public void apply(Project project) {
+    public void apply(Project rootProject) {
         Preconditions.checkState(
-                project == project.getRootProject(),
+                rootProject == rootProject.getRootProject(),
                 "May only apply com.palantir.java-format-provider to the root project");
 
-        JavaFormatExtension extension =
-                project.getExtensions().create("palantirJavaFormat", JavaFormatExtension.class, project);
-
-        project.getConfigurations().create(CONFIGURATION_NAME, conf -> {
+        Configuration configuration = rootProject.getConfigurations().create(CONFIGURATION_NAME, conf -> {
             conf.setDescription("Internal configuration for resolving the palantir-java-format implementation");
             conf.setVisible(false);
             conf.setCanBeConsumed(false);
-            // Using addLater instead of afterEvaluate, in order to delay reading the extension until after the user
-            // has configured it.
-            conf.defaultDependencies(deps -> deps.addLater(project.provider(() -> {
-                String version = extension.getImplementationVersion().get();
 
-                return project.getDependencies().create(ImmutableMap.of(
+            conf.defaultDependencies(deps -> {
+                deps.add(rootProject.getDependencies().create(ImmutableMap.of(
                         "group", "com.palantir.javaformat",
                         "name", "palantir-java-format",
-                        "version", version));
-            })));
+                        "version", JavaFormatExtension.class.getPackage().getImplementationVersion())));
+            });
         });
+
+        rootProject.getExtensions().create("palantirJavaFormat", JavaFormatExtension.class, configuration);
     }
 }