Merge pull request #9839 from kashike

* gh-9839:
  Polish "Use -parameters compiler arg by default in Gradle builds"
  Use -parameters compiler arg by default in Gradle builds

spring-boot-tools/spring-boot-gradle-plugin/src/main/asciidoc/reacting.adoc

@@ -21,6 +21,7 @@ plugin:
 5. Creates a configuration named `bootArchives` that contains the artifact produced by
    the `bootJar` task.
 6. Configures any `JavaCompile` tasks with no configured encoding to use `UTF-8`.
+7. Configures any `JavaCompile` tasks to use the `-parameters` compiler argument.
 
 
 

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/plugin/JavaPluginAction.java

@@ -17,6 +17,7 @@
 package org.springframework.boot.gradle.plugin;
 
 import java.util.Collections;
+import java.util.List;
 import java.util.concurrent.Callable;
 
 import org.gradle.api.Action;
@@ -41,6 +42,7 @@ import org.springframework.boot.gradle.tasks.run.BootRun;
  */
 final class JavaPluginAction implements PluginApplicationAction {
 
+	private static final String PARAMETERS_COMPILER_ARG = "-parameters";
 	private final SinglePublishedArtifact singlePublishedArtifact;
 
 	JavaPluginAction(SinglePublishedArtifact singlePublishedArtifact) {
@@ -60,6 +62,7 @@ final class JavaPluginAction implements PluginApplicationAction {
 		configureArtifactPublication(project, bootJar);
 		configureBootRunTask(project);
 		configureUtf8Encoding(project);
+		configureParametersCompilerArg(project);
 	}
 
 	private void disableJarTask(Project project) {
@@ -121,4 +124,13 @@ final class JavaPluginAction implements PluginApplicationAction {
 				}));
 	}
 
+	private void configureParametersCompilerArg(Project project) {
+		project.getTasks().withType(JavaCompile.class, (compile) -> {
+			List<String> compilerArgs = compile.getOptions().getCompilerArgs();
+			if (!compilerArgs.contains(PARAMETERS_COMPILER_ARG)) {
+				compilerArgs.add(PARAMETERS_COMPILER_ARG);
+			}
+		});
+	}
+
 }

spring-boot-tools/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/plugin/JavaPluginActionIntegrationTests.java

@@ -73,6 +73,27 @@ public class JavaPluginActionIntegrationTests {
 						.contains("compileTestJava = UTF-8");
 	}
 
+	@Test
+	public void javaCompileTasksUseParametersCompilerFlagByDefault() {
+		assertThat(this.gradleBuild.build("javaCompileTasksCompilerArgs").getOutput())
+				.contains("compileJava compiler args: [-parameters]")
+				.contains("compileTestJava compiler args: [-parameters]");
+	}
+
+	@Test
+	public void javaCompileTasksUseParametersAndAdditionalCompilerFlags() {
+		assertThat(this.gradleBuild.build("javaCompileTasksCompilerArgs").getOutput())
+				.contains("compileJava compiler args: [-parameters, -Xlint:all]")
+				.contains("compileTestJava compiler args: [-parameters, -Xlint:all]");
+	}
+
+	@Test
+	public void javaCompileTasksCanOverrideDefaultParametersCompilerFlag() {
+		assertThat(this.gradleBuild.build("javaCompileTasksCompilerArgs").getOutput())
+				.contains("compileJava compiler args: [-Xlint:all]")
+				.contains("compileTestJava compiler args: [-Xlint:all]");
+	}
+
 	@Test
 	public void assembleRunsBootJarAndJarIsSkipped() {
 		BuildResult result = this.gradleBuild.build("assemble");

spring-boot-tools/spring-boot-gradle-plugin/src/test/resources/org/springframework/boot/gradle/plugin/JavaPluginActionIntegrationTests-javaCompileTasksCanOverrideDefaultParametersCompilerFlag.gradle

@@ -0,0 +1,21 @@
+buildscript {
+	dependencies {
+		classpath files(pluginClasspath.split(','))
+	}
+}
+
+apply plugin: 'org.springframework.boot'
+apply plugin: 'java'
+
+tasks.withType(JavaCompile) {
+	options.compilerArgs = ['-Xlint:all']
+}
+
+
+task('javaCompileTasksCompilerArgs') {
+	doFirst {
+		tasks.withType(JavaCompile) {
+			println "$name compiler args: ${options.compilerArgs}"
+		}
+	}
+}

spring-boot-tools/spring-boot-gradle-plugin/src/test/resources/org/springframework/boot/gradle/plugin/JavaPluginActionIntegrationTests-javaCompileTasksUseParametersAndAdditionalCompilerFlags.gradle

@@ -0,0 +1,20 @@
+buildscript {
+	dependencies {
+		classpath files(pluginClasspath.split(','))
+	}
+}
+
+apply plugin: 'org.springframework.boot'
+apply plugin: 'java'
+
+tasks.withType(JavaCompile) {
+	options.compilerArgs << '-Xlint:all'
+}
+
+task('javaCompileTasksCompilerArgs') {
+	doFirst {
+		tasks.withType(JavaCompile) {
+			println "$name compiler args: ${options.compilerArgs}"
+		}
+	}
+}

spring-boot-tools/spring-boot-gradle-plugin/src/test/resources/org/springframework/boot/gradle/plugin/JavaPluginActionIntegrationTests-javaCompileTasksUseParametersCompilerFlagByDefault.gradle

@@ -0,0 +1,16 @@
+buildscript {
+	dependencies {
+		classpath files(pluginClasspath.split(','))
+	}
+}
+
+apply plugin: 'org.springframework.boot'
+apply plugin: 'java'
+
+task('javaCompileTasksCompilerArgs') {
+	doFirst {
+		tasks.withType(JavaCompile) {
+			println "$name compiler args: ${options.compilerArgs}"
+		}
+	}
+}