Merge branch '3.5.x'

Closes gh-47783

core/spring-boot/src/main/java/org/springframework/boot/SpringApplicationAotProcessor.java

@@ -58,12 +58,27 @@ public class SpringApplicationAotProcessor extends ContextAotProcessor {
 	@Override
 	protected GenericApplicationContext prepareApplicationContext(Class<?> application) {
 		return new AotProcessorHook(application).run(() -> {
-			Method mainMethod = application.getMethod("main", String[].class);
-			ReflectionUtils.invokeMethod(mainMethod, null, new Object[] { this.applicationArgs });
+			Method mainMethod = getMainMethod(application);
+			mainMethod.setAccessible(true);
+			if (mainMethod.getParameterCount() == 0) {
+				ReflectionUtils.invokeMethod(mainMethod, null);
+			}
+			else {
+				ReflectionUtils.invokeMethod(mainMethod, null, new Object[] { this.applicationArgs });
+			}
 			return Void.class;
 		});
 	}
 
+	private static Method getMainMethod(Class<?> application) throws Exception {
+		try {
+			return application.getDeclaredMethod("main", String[].class);
+		}
+		catch (NoSuchMethodException ex) {
+			return application.getDeclaredMethod("main");
+		}
+	}
+
 	public static void main(String[] args) throws Exception {
 		int requiredArgs = 6;
 		Assert.state(args.length >= requiredArgs, () -> "Usage: " + SpringApplicationAotProcessor.class.getName()

core/spring-boot/src/test/java/org/springframework/boot/SpringApplicationAotProcessorTests.java

@@ -37,20 +37,21 @@ import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
  */
 class SpringApplicationAotProcessorTests {
 
+	private static final ApplicationInvoker invoker = new ApplicationInvoker();
+
 	@BeforeEach
 	void setup() {
-		SampleApplication.argsHolder = null;
-		SampleApplication.postRunInvoked = false;
+		invoker.clean();
 	}
 
 	@Test
-	void processApplicationInvokesRunMethod(@TempDir Path directory) {
+	void processApplicationInvokesMainMethod(@TempDir Path directory) {
 		String[] arguments = new String[] { "1", "2" };
-		SpringApplicationAotProcessor processor = new SpringApplicationAotProcessor(SampleApplication.class,
+		SpringApplicationAotProcessor processor = new SpringApplicationAotProcessor(PublicMainMethod.class,
 				settings(directory), arguments);
 		processor.process();
-		assertThat(SampleApplication.argsHolder).isEqualTo(arguments);
-		assertThat(SampleApplication.postRunInvoked).isFalse();
+		assertThat(ApplicationInvoker.argsHolder).isEqualTo(arguments);
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
 	}
 
 	@Test
@@ -63,23 +64,53 @@ class SpringApplicationAotProcessorTests {
 	}
 
 	@Test
-	void invokeMainParsesArgumentsAndInvokesRunMethod(@TempDir Path directory) throws Exception {
-		String[] mainArguments = new String[] { SampleApplication.class.getName(),
+	void invokeMainParsesArgumentsAndInvokesMainMethod(@TempDir Path directory) throws Exception {
+		String[] mainArguments = new String[] { PublicMainMethod.class.getName(),
+				directory.resolve("source").toString(), directory.resolve("resource").toString(),
+				directory.resolve("class").toString(), "com.example", "example", "1", "2" };
+		SpringApplicationAotProcessor.main(mainArguments);
+		assertThat(ApplicationInvoker.argsHolder).containsExactly("1", "2");
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
+	}
+
+	@Test
+	void invokeMainParsesArgumentsAndInvokesPackagePrivateMainMethod(@TempDir Path directory) throws Exception {
+		String[] mainArguments = new String[] { PackagePrivateMainMethod.class.getName(),
 				directory.resolve("source").toString(), directory.resolve("resource").toString(),
 				directory.resolve("class").toString(), "com.example", "example", "1", "2" };
 		SpringApplicationAotProcessor.main(mainArguments);
-		assertThat(SampleApplication.argsHolder).containsExactly("1", "2");
-		assertThat(SampleApplication.postRunInvoked).isFalse();
+		assertThat(ApplicationInvoker.argsHolder).containsExactly("1", "2");
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
+	}
+
+	@Test
+	void invokeMainParsesArgumentsAndInvokesParameterLessMainMethod(@TempDir Path directory) throws Exception {
+		String[] mainArguments = new String[] { PublicParameterlessMainMethod.class.getName(),
+				directory.resolve("source").toString(), directory.resolve("resource").toString(),
+				directory.resolve("class").toString(), "com.example", "example", "1", "2" };
+		SpringApplicationAotProcessor.main(mainArguments);
+		assertThat(ApplicationInvoker.argsHolder).isNull();
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
+	}
+
+	@Test
+	void invokeMainParsesArgumentsAndInvokesPackagePrivateRunMethod(@TempDir Path directory) throws Exception {
+		String[] mainArguments = new String[] { PackagePrivateParameterlessMainMethod.class.getName(),
+				directory.resolve("source").toString(), directory.resolve("resource").toString(),
+				directory.resolve("class").toString(), "com.example", "example", "1", "2" };
+		SpringApplicationAotProcessor.main(mainArguments);
+		assertThat(ApplicationInvoker.argsHolder).isNull();
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
 	}
 
 	@Test
 	void invokeMainParsesArgumentsAndInvokesRunMethodWithoutGroupId(@TempDir Path directory) throws Exception {
-		String[] mainArguments = new String[] { SampleApplication.class.getName(),
+		String[] mainArguments = new String[] { PublicMainMethod.class.getName(),
 				directory.resolve("source").toString(), directory.resolve("resource").toString(),
 				directory.resolve("class").toString(), "", "example", "1", "2" };
 		SpringApplicationAotProcessor.main(mainArguments);
-		assertThat(SampleApplication.argsHolder).containsExactly("1", "2");
-		assertThat(SampleApplication.postRunInvoked).isFalse();
+		assertThat(ApplicationInvoker.argsHolder).containsExactly("1", "2");
+		assertThat(ApplicationInvoker.postRunInvoked).isFalse();
 	}
 
 	@Test
@@ -100,16 +131,37 @@ class SpringApplicationAotProcessorTests {
 	}
 
 	@Configuration(proxyBeanMethods = false)
-	public static class SampleApplication {
+	public static class PublicMainMethod {
 
-		public static String @Nullable [] argsHolder;
+		public static void main(String[] args) {
+			invoker.invoke(args, () -> SpringApplication.run(PublicMainMethod.class, args));
+		}
 
-		public static boolean postRunInvoked;
+	}
 
-		public static void main(String[] args) {
-			argsHolder = args;
-			SpringApplication.run(SampleApplication.class, args);
-			postRunInvoked = true;
+	@Configuration(proxyBeanMethods = false)
+	public static class PackagePrivateMainMethod {
+
+		static void main(String[] args) {
+			invoker.invoke(args, () -> SpringApplication.run(PackagePrivateMainMethod.class, args));
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	public static class PublicParameterlessMainMethod {
+
+		public static void main() {
+			invoker.invoke(null, () -> SpringApplication.run(PublicParameterlessMainMethod.class));
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	public static class PackagePrivateParameterlessMainMethod {
+
+		static void main() {
+			invoker.invoke(null, () -> SpringApplication.run(PackagePrivateParameterlessMainMethod.class));
 		}
 
 	}
@@ -122,4 +174,23 @@ class SpringApplicationAotProcessorTests {
 
 	}
 
+	private static final class ApplicationInvoker {
+
+		public static String @Nullable [] argsHolder;
+
+		public static boolean postRunInvoked;
+
+		void invoke(String @Nullable [] args, Runnable applicationRun) {
+			argsHolder = args;
+			applicationRun.run();
+			postRunInvoked = true;
+		}
+
+		void clean() {
+			argsHolder = null;
+			postRunInvoked = false;
+		}
+
+	}
+
 }