Revise @⁠AutoClose implementation

Closes junit-team#3367
Closes junit-team#3592

documentation/src/docs/asciidoc/link-attributes.adoc

@@ -68,6 +68,7 @@ endif::[]
 :api-package:                                {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/package-summary.html[org.junit.jupiter.api]
 :Assertions:                                 {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/Assertions.html[org.junit.jupiter.api.Assertions]
 :Assumptions:                                {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/Assumptions.html[org.junit.jupiter.api.Assumptions]
+:AutoClose:                                  {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/AutoClose.html[@AutoClose]
 :ClassOrderer_ClassName:                     {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/ClassOrderer.ClassName.html[ClassOrderer.ClassName]
 :ClassOrderer_DisplayName:                   {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/ClassOrderer.DisplayName.html[ClassOrderer.DisplayName]
 :ClassOrderer_OrderAnnotation:               {javadoc-root}/org.junit.jupiter.api/org/junit/jupiter/api/ClassOrderer.OrderAnnotation.html[ClassOrderer.OrderAnnotation]
@@ -153,7 +154,7 @@ endif::[]
 // Jupiter Engine
 :junit-jupiter-engine:                       {javadoc-root}/org.junit.jupiter.engine/org/junit/jupiter/engine/package-summary.html[junit-jupiter-engine]
 // Jupiter Extension Implementations
-:AutoCloseExtension:                         {current-branch}/junit-jupiter-api/src/main/java/org/junit/jupiter/api/AutoCloseExtension.java[AutoCloseExtension]
+:AutoCloseExtension:                         {current-branch}/junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/extension/AutoCloseExtension.java[AutoCloseExtension]
 :DisabledCondition:                          {current-branch}/junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/extension/DisabledCondition.java[DisabledCondition]
 :RepetitionExtension:                        {current-branch}/junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/extension/RepetitionExtension.java[RepetitionExtension]
 :TempDirectory:                              {current-branch}/junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/extension/TempDirectory.java[TempDirectory]

documentation/src/docs/asciidoc/release-notes/release-notes-5.11.0-M1.adoc

@@ -45,8 +45,8 @@ repository on GitHub.
 
 ==== New Features and Improvements
 
-* The new `@AutoClose` annotation can be applied to fields within tests to automatically
-  close the annotated resource after test execution. See
+* New `@AutoClose` annotation that can be applied to fields within tests to automatically
+  close the annotated resource after test execution. See the
   <<../user-guide/index.adoc#writing-tests-built-in-extensions-AutoClose, User Guide>> for
   details.
 

documentation/src/docs/asciidoc/user-guide/writing-tests.adoc

@@ -41,11 +41,11 @@ in the `junit-jupiter-api` module.
 | `@Nested`                | Denotes that the annotated class is a non-static <<writing-tests-nested,nested test class>>. On Java 8 through Java 15, `@BeforeAll` and `@AfterAll` methods cannot be used directly in a `@Nested` test class unless the "per-class" <<writing-tests-test-instance-lifecycle, test instance lifecycle>> is used. Beginning with Java 16, `@BeforeAll` and `@AfterAll` methods can be declared as `static` in a `@Nested` test class with either test instance lifecycle mode. Such annotations are not _inherited_.
 | `@Tag`                   | Used to declare <<writing-tests-tagging-and-filtering,tags for filtering tests>>, either at the class or method level; analogous to test groups in TestNG or Categories in JUnit 4. Such annotations are _inherited_ at the class level but not at the method level.
 | `@Disabled`              | Used to <<writing-tests-disabling,disable>> a test class or test method; analogous to JUnit 4's `@Ignore`. Such annotations are not _inherited_.
+| `@AutoClose`             | Denotes that the annotated field represents a resource that will be <<writing-tests-built-in-extensions-AutoClose,automatically closed>> after test execution.
 | `@Timeout`               | Used to fail a test, test factory, test template, or lifecycle method if its execution exceeds a given duration. Such annotations are _inherited_.
+| `@TempDir`               | Used to supply a <<writing-tests-built-in-extensions-TempDirectory,temporary directory>> via field injection or parameter injection in a lifecycle method or test method; located in the `org.junit.jupiter.api.io` package.
 | `@ExtendWith`            | Used to <<extensions-registration-declarative,register extensions declaratively>>. Such annotations are _inherited_.
 | `@RegisterExtension`     | Used to <<extensions-registration-programmatic,register extensions programmatically>> via fields. Such fields are _inherited_ unless they are _shadowed_.
-| `@TempDir`               | Used to supply a <<writing-tests-built-in-extensions-TempDirectory,temporary directory>> via field injection or parameter injection in a lifecycle method or test method; located in the `org.junit.jupiter.api.io` package.
-| `@AutoClose`             | Denotes that the annotated field represents a resource that should be automatically closed after test execution.
 |===
 
 WARNING: Some annotations may currently be _experimental_. Consult the table in
@@ -2573,12 +2573,12 @@ include::{testDir}/example/SharedResourcesDemo.java[tags=user_guide]
 === Built-in Extensions
 
 While the JUnit team encourages reusable extensions to be packaged and maintained in
-separate libraries, the JUnit Jupiter API artifact includes a few user-facing extension
-implementations that are considered so generally useful that users shouldn't have to add
-another dependency.
+separate libraries, JUnit Jupiter includes a few user-facing extension implementations
+that are considered so generally useful that users shouldn't have to add another
+dependency.
 
 [[writing-tests-built-in-extensions-TempDirectory]]
-==== The TempDirectory Extension
+==== The @TempDir Extension
 
 The built-in `{TempDirectory}` extension is used to create and clean up a temporary
 directory for an individual test or all tests in a test class. It is registered by
@@ -2712,24 +2712,48 @@ parameter, if present
 3. Otherwise, `org.junit.jupiter.api.io.TempDirFactory$Standard` will be used.
 
 [[writing-tests-built-in-extensions-AutoClose]]
-==== The AutoClose Extension
-
-The built-in `{AutoCloseExtension}` is used to automatically close resources used in
-tests. Therefore, the `@AutoClose` annotation is applied to fields within the
-test class to indicate that the annotated resource should be automatically closed after
-the test execution.
-
-By default, the `@AutoClose` annotation expects the annotated resource to provide
-a `close()` method that will be invoked for closing the resource. However, developers
-can customize the closing behavior by providing a different method name through the
-`value` attribute. For example, setting `value = "shutdown"` will look
-for a method named `shutdown()` to close the resource.
-
-For example, the following test declares a database connection field annotated with
-`@AutoClose` that is automatically closed afterward.
-
-[source,java,indent=0]
-.A test class using @AutoClose annotation to close used resource
+==== The @AutoClose Extension
+
+The built-in `{AutoCloseExtension}` automatically closes resources associated with fields.
+It is registered by default. To use it, annotate a field in a test class with
+`{AutoClose}`.
+
+`@AutoClose` fields may be either `static` or non-static. If the value of an `@AutoClose`
+field is `null` when it is evaluated the field will be ignored, but a warning message will
+be logged to inform you.
+
+By default, `@AutoClose` expects the value of the annotated field to implement a `close()`
+method that will be invoked to close the resource. However, developers can customize the
+name of the close method via the `value` attribute. For example, `@AutoClose("shutdown")`
+instructs JUnit to look for a `shutdown()` method to close the resource.
+
+`@AutoClose` fields are inherited from superclasses as long as they are not hidden.
+Furthermore, `@AutoClose` fields from subclasses will be closed before `@AutoClose` fields
+in superclasses.
+
+When multiple `@AutoClose` fields exist within a given test class, the order in which the
+resources are closed depends on an algorithm that is deterministic but intentionally
+nonobvious. This ensures that subsequent runs of a test suite close resources in the same
+order, thereby allowing for repeatable builds.
+
+The extension that closes `@AutoClose` fields implements the `AfterAllCallback` and
+`TestInstancePreDestroyCallback` extension APIs. Consequently, a `static` `@AutoClose`
+field will be closed after all tests in the current test class have completed, effectively
+after `@AfterAll` methods have executed for the test class. A non-static `@AutoClose`
+field will be closed before the current test class instance is destroyed. Specifically, if
+the test class is configured with `@TestInstance(Lifecycle.PER_METHOD)` semantics, a
+non-static `@AutoClose` field will be closed after the execution of each test method, test
+factory method, or test template method. However, if the test class is configured with
+`@TestInstance(Lifecycle.PER_CLASS)` semantics, a non-static `@AutoClose` field will not
+be closed until the current test class instance is no longer needed, which means after
+`@AfterAll` methods and after all `static` `@AutoClose` fields have been closed.
+
+The following example demonstrates how to annotate an instance field with `@AutoClose` so
+that the resource is automatically closed after test execution. Note that `WebClient`
+implements `java.lang.AutoCloseable` which defines a `close()` method.
+
+[source,java,indent=0]
+.A test class using `@AutoClose` to close a resource
 ----
 include::{testDir}/example/AutoCloseDemo.java[tags=user_guide_example]
 ----

documentation/src/main/java/example/registration/WebClient.java

@@ -10,10 +10,15 @@
 
 package example.registration;
 
-public class WebClient {
+public class WebClient implements AutoCloseable {
 
 	public WebResponse get(String string) {
 		return new WebResponse();
 	}
 
+	@Override
+	public void close() {
+		/* no-op for demo */
+	}
+
 }

documentation/src/test/java/example/AutoCloseDemo.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2023 the original author or authors.
+ * Copyright 2015-2024 the original author or authors.
  *
  * All rights reserved. This program and the accompanying materials are
  * made available under the terms of the Eclipse Public License v2.0 which
@@ -10,40 +10,30 @@
 
 package example;
 
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-import java.sql.Connection;
-import java.sql.DriverManager;
-import java.sql.ResultSet;
-import java.sql.SQLException;
+import example.registration.WebClient;
 
 import org.junit.jupiter.api.AutoClose;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
-@Disabled
 // tag::user_guide_example[]
 class AutoCloseDemo {
 
+	// WebClient implements AutoCloseable
 	@AutoClose
-	Connection connection = getJdbcConnection("jdbc:mysql://localhost/testdb");
+	WebClient webClient = new WebClient();
 
-	@Test
-	void usersTableHasEntries() throws SQLException {
-		ResultSet resultSet = connection.createStatement().executeQuery("SELECT * FROM users");
-
-		assertTrue(resultSet.next());
-	}
+	String serverUrl = // specify server URL ...
+		// end::user_guide_example[]
+		"https://localhost";
+	// tag::user_guide_example[]
 
-	// ...
-	// end::user_guide_example[]
-	private static Connection getJdbcConnection(String url) {
-		try {
-			return DriverManager.getConnection(url);
-		}
-		catch (SQLException ex) {
-			throw new RuntimeException(ex);
-		}
+	@Test
+	void getProductList() {
+		// Use WebClient to connect to web server and verify response
+		assertEquals(200, webClient.get(serverUrl + "/products").getResponseStatus());
 	}
 
 }
+// end::user_guide_example[]

documentation/src/test/java/example/registration/WebServerDemo.java

@@ -31,6 +31,9 @@ class WebServerDemo {
 
 	@Test
 	void getProductList() {
+		// end::user_guide[]
+		@SuppressWarnings("resource")
+		// tag::user_guide[]
 		WebClient webClient = new WebClient();
 		String serverUrl = server.getServerUrl();
 		// Use WebClient to connect to web server using serverUrl and verify response

junit-jupiter-api/src/main/java/org/junit/jupiter/api/AutoClose.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2023 the original author or authors.
+ * Copyright 2015-2024 the original author or authors.
  *
  * All rights reserved. This program and the accompanying materials are
  * made available under the terms of the Eclipse Public License v2.0 which
@@ -10,49 +10,84 @@
 
 package org.junit.jupiter.api;
 
+import static org.apiguardian.api.API.Status.EXPERIMENTAL;
+
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 import org.apiguardian.api.API;
-import org.junit.jupiter.api.extension.ExtendWith;
 
 /**
- * The {@code AutoClose} annotation is used to automatically close resources
- * used in tests.
+ * {@code @AutoClose} is used to indicate that an annotated field will be
+ * automatically closed after test execution.
+ *
+ * <p>{@code @AutoClose} fields may be either {@code static} or non-static. If
+ * the value of an {@code @AutoClose} field is {@code null} when it is evaluated
+ * the field will be ignored, but a warning message will be logged to inform you.
+ *
+ * <p>By default, {@code @AutoClose} expects the value of the annotated field to
+ * implement a {@code close()} method that will be invoked to close the resource.
+ * However, developers can customize the name of the {@code close} method via the
+ * {@link #value} attribute. For example, {@code @AutoClose("shutdown")} instructs
+ * JUnit to look for a {@code shutdown()} method to close the resource.
+ *
+ * <p>{@code @AutoClose} may be used as a meta-annotation in order to create a
+ * custom <em>composed annotation</em> that inherits the semantics of
+ * {@code @AutoClose}.
+ *
+ * <h2>Inheritance</h2>
+ *
+ * <p>{@code @AutoClose} fields are inherited from superclasses as long as they
+ * are not <em>hidden</em>. Furthermore, {@code @AutoClose} fields from subclasses
+ * will be closed before {@code @AutoClose} fields in superclasses.
+ *
+ * <h2>Evaluation Order</h2>
+ *
+ * <p>When multiple {@code @AutoClose} fields exist within a given test class,
+ * the order in which the resources are closed depends on an algorithm that is
+ * deterministic but intentionally nonobvious. This ensures that subsequent runs
+ * of a test suite close resources in the same order, thereby allowing for
+ * repeatable builds.
  *
- * <p>This annotation should be applied to fields within test classes. It
- * indicates that the annotated resource should be automatically closed after
- * the test execution.
+ * <h2>Scope and Lifecycle</h2>
  *
- * <p>By default, the {@code AutoClose} annotation expects the annotated
- * resource to provide a {@code close()} method that will be invoked for closing
- * the resource. However, developers can customize the closing behavior by
- * providing a different method name through the {@link #value} attribute. For
- * example, setting {@code value = "shutdown"} will look for a method named
- * {@code shutdown()} to close the resource. When multiple annotated resources
- * exist the order of closing them is unspecified.
+ * <p>The extension that closes {@code @AutoClose} fields implements the
+ * {@link org.junit.jupiter.api.extension.AfterAllCallback AfterAllCallback} and
+ * {@link org.junit.jupiter.api.extension.TestInstancePreDestroyCallback
+ * TestInstancePreDestroyCallback} extension APIs. Consequently, a {@code static}
+ * {@code @AutoClose} field will be closed after all tests in the current test
+ * class have completed, effectively after {@code @AfterAll} methods have executed
+ * for the test class. A non-static {@code @AutoClose} field will be closed before
+ * the current test class instance is destroyed. Specifically, if the test class
+ * is configured with
+ * {@link TestInstance.Lifecycle#PER_METHOD @TestInstance(Lifecycle.PER_METHOD)}
+ * semantics, a non-static {@code @AutoClose} field will be closed after the
+ * execution of each test method, test factory method, or test template method.
+ * However, if the test class is configured with
+ * {@link TestInstance.Lifecycle#PER_CLASS @TestInstance(Lifecycle.PER_CLASS)}
+ * semantics, a non-static {@code @AutoClose} field will not be closed until the
+ * current test class instance is no longer needed, which means after
+ * {@code @AfterAll} methods and after all {@code static} {@code @AutoClose} fields
+ * have been closed.
  *
  * @since 5.11
- * @see java.lang.annotation.Retention
- * @see java.lang.annotation.Target
  */
-@Target(ElementType.FIELD)
+@Target({ ElementType.ANNOTATION_TYPE, ElementType.FIELD })
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
-@ExtendWith(AutoCloseExtension.class)
-@API(status = API.Status.EXPERIMENTAL, since = "5.11")
-@SuppressWarnings("exports")
+@API(status = EXPERIMENTAL, since = "5.11")
 public @interface AutoClose {
 
 	/**
-	 * Specifies the name of the method to invoke for closing the resource.
+	 * Specify the name of the method to invoke to close the resource.
 	 *
-	 * <p>The default value is {@code close}.
+	 * <p>The default value is {@code "close"} which works with any type that
+	 * implements {@link AutoCloseable} or has a {@code close()} method.
 	 *
-	 * @return the method name for closing the resource
+	 * @return the name of the method to invoke to close the resource
 	 */
 	String value() default "close";