BlockHoundIntegration for spring-core

build.gradle

@@ -64,6 +64,8 @@ configure(allprojects) { project ->
  dependency "io.reactivex:rxjava-reactive-streams:1.2.1"
  dependency "io.reactivex.rxjava2:rxjava:2.2.17"
 
+ dependency "io.projectreactor.tools:blockhound:1.0.2.RELEASE"
+
  dependency "com.caucho:hessian:4.0.62"
  dependency "com.fasterxml:aalto-xml:1.2.2"
  dependency("com.fasterxml.woodstox:woodstox-core:6.0.3") {

spring-core/spring-core.gradle

@@ -43,6 +43,7 @@ dependencies {
  compile(files(objenesisRepackJar))
  compile(project(":spring-jcl"))
  compileOnly(project(":kotlin-coroutines"))
+ compileOnly("io.projectreactor.tools:blockhound")
  optional("net.sf.jopt-simple:jopt-simple")
  optional("org.aspectj:aspectjweaver")
  optional("org.jetbrains.kotlin:kotlin-reflect")
@@ -60,6 +61,7 @@ dependencies {
  testCompile("javax.xml.bind:jaxb-api")
  testCompile("com.fasterxml.woodstox:woodstox-core")
  testCompile(project(":kotlin-coroutines"))
+ testCompile("io.projectreactor.tools:blockhound")
  testFixturesImplementation("com.google.code.findbugs:jsr305")
  testFixturesImplementation("io.projectreactor:reactor-test")
  testFixturesImplementation("org.assertj:assertj-core")

spring-core/src/main/java/org/springframework/core/ReactiveAdapterRegistry.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -29,12 +29,15 @@
 import kotlinx.coroutines.CompletableDeferredKt;
 import kotlinx.coroutines.Deferred;
 import org.reactivestreams.Publisher;
+import reactor.blockhound.BlockHound;
+import reactor.blockhound.integration.BlockHoundIntegration;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import rx.RxReactiveStreams;
 
 import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
+import org.springframework.util.ConcurrentReferenceHashMap;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -354,4 +357,32 @@ void registerAdapters(ReactiveAdapterRegistry registry) {
  );
  }
  }
+
+
+ /**
+ * {@code BlockHoundIntegration} for spring-core classes.
+ * <p>Whitelists the following:
+ * <ul>
+ * <li>Reading class info via {@link LocalVariableTableParameterNameDiscoverer}.
+ * <li>Locking within {@link ConcurrentReferenceHashMap}.
+ * </ul>
+ * @since 5.2.4
+ */
+ public static class SpringCoreBlockHoundIntegration implements BlockHoundIntegration {
+
+ @Override
+ public void applyTo(BlockHound.Builder builder) {
+
+ // Avoid hard references potentially anywhere in spring-core (no need for structural dependency)
+
+ builder.allowBlockingCallsInside(
+ "org.springframework.core.LocalVariableTableParameterNameDiscoverer", "inspectClass");
+
+ String className = "org.springframework.util.ConcurrentReferenceHashMap$Segment";
+ builder.allowBlockingCallsInside(className, "doTask");
+ builder.allowBlockingCallsInside(className, "clear");
+ builder.allowBlockingCallsInside(className, "restructure");
+ }
+ }
+
 }

spring-core/src/main/resources/META-INF/services/reactor.blockhound.integration.BlockHoundIntegration

@@ -0,0 +1,15 @@
+# Copyright 2002-2020 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.
+
+org.springframework.core.ReactiveAdapterRegistry$SpringCoreBlockHoundIntegration

spring-core/src/test/java/org/springframework/core/SpringCoreBlockHoundIntegrationTests.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright 2002-2020 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.core;
+
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import reactor.blockhound.BlockHound;
+import reactor.core.scheduler.Schedulers;
+
+import org.springframework.tests.sample.objects.TestObject;
+import org.springframework.util.ConcurrentReferenceHashMap;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * Tests to verify the spring-core BlockHound integration rules.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.2.4
+ */
+public class SpringCoreBlockHoundIntegrationTests {
+
+
+ @BeforeAll
+ static void setUp() {
+ BlockHound.install();
+ }
+
+
+ @Test
+ void blockHoundIsInstalled() {
+ assertThatThrownBy(() -> testNonBlockingTask(() -> Thread.sleep(10)))
+ .hasMessageContaining("Blocking call!");
+ }
+
+ @Test
+ void localVariableTableParameterNameDiscoverer() {
+ testNonBlockingTask(() -> {
+ Method setName = TestObject.class.getMethod("setName", String.class);
+ String[] names = new LocalVariableTableParameterNameDiscoverer().getParameterNames(setName);
+ assertThat(names).isEqualTo(new String[] {"name"});
+ });
+ }
+
+ @Test
+ void concurrentReferenceHashMap() {
+ int size = 10000;
+ Map<String, String> map = new ConcurrentReferenceHashMap<>(size);
+
+ CompletableFuture<Object> future1 = new CompletableFuture<>();
+ testNonBlockingTask(() -> {
+ for (int i = 0; i < size / 2; i++) {
+ map.put("a" + i, "bar");
+ }
+ }, future1);
+
+ CompletableFuture<Object> future2 = new CompletableFuture<>();
+ testNonBlockingTask(() -> {
+ for (int i = 0; i < size / 2; i++) {
+ map.put("b" + i, "bar");
+ }
+ }, future2);
+
+ CompletableFuture.allOf(future1, future2).join();
+ assertThat(map).hasSize(size);
+ }
+
+ private void testNonBlockingTask(NonBlockingTask task) {
+ CompletableFuture<Object> future = new CompletableFuture<>();
+ testNonBlockingTask(task, future);
+ future.join();
+ }
+
+ private void testNonBlockingTask(NonBlockingTask task, CompletableFuture<Object> future) {
+ Schedulers.parallel().schedule(() -> {
+ try {
+ task.run();
+ future.complete(null);
+ }
+ catch (Throwable ex) {
+ future.completeExceptionally(ex);
+ }
+ });
+ }
+
+
+ @FunctionalInterface
+ private interface NonBlockingTask {
+
+ void run() throws Exception;
+ }
+
+}