Support @Inject from JSR-330 & Jakarta for autowiring test constructors

See gh-29851

spring-test/spring-test.gradle

@@ -70,6 +70,7 @@ dependencies {
 	testImplementation("jakarta.mail:jakarta.mail-api")
 	testImplementation("jakarta.validation:jakarta.validation-api")
 	testImplementation("javax.cache:cache-api")
+	testImplementation("javax.inject:javax.inject:1")
 	testImplementation("org.apache.httpcomponents:httpclient") {
 		exclude group: "commons-logging", module: "commons-logging"
 	}

spring-test/src/main/java/org/springframework/test/context/support/TestConstructorUtils.java

@@ -16,8 +16,11 @@
 
 package org.springframework.test.context.support;
 
+import java.lang.annotation.Annotation;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Executable;
+import java.util.LinkedHashSet;
+import java.util.Set;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.core.SpringProperties;
@@ -26,6 +29,7 @@ import org.springframework.lang.Nullable;
 import org.springframework.test.context.TestConstructor;
 import org.springframework.test.context.TestConstructor.AutowireMode;
 import org.springframework.test.context.TestContextAnnotationUtils;
+import org.springframework.util.ClassUtils;
 
 /**
  * Utility methods for working with {@link TestConstructor @TestConstructor}.
@@ -33,6 +37,7 @@ import org.springframework.test.context.TestContextAnnotationUtils;
  * <p>Primarily intended for use within the framework.
  *
  * @author Sam Brannen
+ * @author Florian Lehmann
  * @since 5.2
  * @see TestConstructor
  */
@@ -99,6 +104,7 @@ public abstract class TestConstructorUtils {
 	 *
 	 * <ol>
 	 * <li>The constructor is annotated with {@link Autowired @Autowired}.</li>
+	 * <li>The constructor is annotated with {@link jakarta.inject.Inject} or {@code javax.inject.Inject}.</li>
 	 * <li>{@link TestConstructor @TestConstructor} is <em>present</em> or
 	 * <em>meta-present</em> on the test class with
 	 * {@link TestConstructor#autowireMode() autowireMode} set to
@@ -119,8 +125,8 @@ public abstract class TestConstructorUtils {
 	public static boolean isAutowirableConstructor(Constructor<?> constructor, Class<?> testClass,
 			@Nullable PropertyProvider fallbackPropertyProvider) {
 
-		// Is the constructor annotated with @Autowired?
-		if (AnnotatedElementUtils.hasAnnotation(constructor, Autowired.class)) {
+		// Is the constructor annotated with @Autowired/@Inject?
+		if (isAnnotatedWithAutowiredOrInject(constructor)) {
 			return true;
 		}
 
@@ -146,4 +152,30 @@ public abstract class TestConstructorUtils {
 		return (autowireMode == AutowireMode.ALL);
 	}
 
+	@SuppressWarnings("unchecked")
+	private static boolean isAnnotatedWithAutowiredOrInject(Constructor<?> constructor) {
+		Set<Class<? extends Annotation>> autowiredAnnotationTypes = new LinkedHashSet<>();
+
+		autowiredAnnotationTypes.add(Autowired.class);
+
+		try {
+			autowiredAnnotationTypes.add((Class<? extends Annotation>)
+					ClassUtils.forName("jakarta.inject.Inject", TestConstructorUtils.class.getClassLoader()));
+		}
+		catch (ClassNotFoundException ex) {
+			// jakarta.inject API not available - simply skip.
+		}
+
+		try {
+			autowiredAnnotationTypes.add((Class<? extends Annotation>)
+					ClassUtils.forName("javax.inject.Inject", TestConstructorUtils.class.getClassLoader()));
+		}
+		catch (ClassNotFoundException ex) {
+			// javax.inject API not available - simply skip.
+		}
+
+		return autowiredAnnotationTypes.stream()
+				.anyMatch(autowiredAnnotationType -> AnnotatedElementUtils.hasAnnotation(constructor, autowiredAnnotationType));
+	}
+
 }

spring-test/src/test/java/org/springframework/test/context/junit/jupiter/InjectAnnotationIntegrationTests.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.context.junit.jupiter;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Common test implementation for integration tests in order to verify support
+ * for {@link jakarta.inject.Inject} and {@link javax.inject.Inject}.
+ *
+ * @author Florian Lehmann
+ * @since 6.0.5
+ */
+@SpringJUnitConfig
+public abstract class InjectAnnotationIntegrationTests {
+
+	private final String foo;
+
+	public InjectAnnotationIntegrationTests(String foo) {
+		this.foo = foo;
+	}
+
+	@Test
+	public void beanInjected() {
+		assertThat(this.foo).isEqualTo("foo");
+	}
+
+	@Configuration
+	static class Config {
+
+		@Bean
+		String foo() {
+			return "foo";
+		}
+
+	}
+}

spring-test/src/test/java/org/springframework/test/context/junit/jupiter/JakartaInjectAnnotationIntegrationTests.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.context.junit.jupiter;
+
+import jakarta.inject.Inject;
+
+/**
+ * Integration tests which verify support for {@link jakarta.inject.Inject}.
+ *
+ * @author Florian Lehmann
+ * @since 6.0.5
+ */
+@SpringJUnitConfig
+public class JakartaInjectAnnotationIntegrationTests extends InjectAnnotationIntegrationTests {
+
+	@Inject
+	public JakartaInjectAnnotationIntegrationTests(String foo) {
+		super(foo);
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/junit/jupiter/JavaxInjectAnnotationIntegrationTests.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.context.junit.jupiter;
+
+import javax.inject.Inject;
+
+/**
+ * Integration tests which verify support for {@link javax.inject.Inject}.
+ *
+ * @author Florian Lehmann
+ * @since 6.0.5
+ */
+@SpringJUnitConfig
+public class JavaxInjectAnnotationIntegrationTests extends InjectAnnotationIntegrationTests {
+
+	@Inject
+	public JavaxInjectAnnotationIntegrationTests(String foo) {
+		super(foo);
+	}
+
+}