Polish "Disable Hazelcast auto-configuration when Jet is present"

See gh-20729

Author: snicoll

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/hazelcast/HazelcastAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 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.
@@ -19,14 +19,22 @@
 import com.hazelcast.core.HazelcastInstance;
 
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionMessage;
+import org.springframework.boot.autoconfigure.condition.ConditionMessage.Builder;
+import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.SpringBootCondition;
+import org.springframework.boot.autoconfigure.hazelcast.HazelcastAutoConfiguration.HazelcastDataGridCondition;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.ConditionContext;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.springframework.core.io.Resource;
+import org.springframework.core.type.AnnotatedTypeMetadata;
 
 /**
- * {@link EnableAutoConfiguration Auto-configuration} for Hazelcast. Creates a
+ * {@link EnableAutoConfiguration Auto-configuration} for Hazelcast IMDG. Creates a
  * {@link HazelcastInstance} based on explicit configuration or when a default
  * configuration file is found in the environment.
  *
@@ -36,10 +44,26 @@
  * @see HazelcastConfigResourceCondition
  */
 @Configuration(proxyBeanMethods = false)
-@Conditional(HazelcastJetConfigMissingCondition.class)
+@Conditional(HazelcastDataGridCondition.class)
 @ConditionalOnClass(HazelcastInstance.class)
 @EnableConfigurationProperties(HazelcastProperties.class)
 @Import({ HazelcastClientConfiguration.class, HazelcastServerConfiguration.class })
 public class HazelcastAutoConfiguration {
 
+	static class HazelcastDataGridCondition extends SpringBootCondition {
+
+		private static final String HAZELCAST_JET_CONFIG_FILE = "classpath:/hazelcast-jet-default.yaml";
+
+		@Override
+		public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
+			Builder message = ConditionMessage.forCondition(HazelcastDataGridCondition.class.getSimpleName());
+			Resource resource = context.getResourceLoader().getResource(HAZELCAST_JET_CONFIG_FILE);
+			if (resource.exists()) {
+				return ConditionOutcome.noMatch(message.because("Found Hazelcast Jet on the classpath"));
+			}
+			return ConditionOutcome.match(message.because("Hazelcast Jet not found on the classpath"));
+		}
+
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/hazelcast/HazelcastJetConfigMissingCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 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.
@@ -16,17 +16,18 @@
 
 package org.springframework.boot.autoconfigure.hazelcast;
 
-import java.net.MalformedURLException;
+import java.io.IOException;
 import java.net.URL;
+import java.net.URLClassLoader;
 
 import com.hazelcast.config.Config;
 import com.hazelcast.core.HazelcastInstance;
-import org.jetbrains.annotations.Nullable;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -52,34 +53,40 @@ void defaultConfigFile() {
 	}
 
 	@Test
-	void testHazelcastInstanceNotCreatedWhenJetIsPresent() {
+	void hazelcastInstanceNotCreatedWhenJetIsPresent() {
 		this.contextRunner.withClassLoader(new JetConfigClassLoader())
 				.run((context) -> assertThat(context).doesNotHaveBean(HazelcastInstance.class));
 	}
 
 	/**
-	 * A specific class loader which emulates that default Hazelcast Jet configuration
-	 * file exists on the classpath.
+	 * A test {link {@link URLClassLoader} that emulates the default Hazelcast Jet
+	 * configuration file exists on the classpath.
 	 */
-	static class JetConfigClassLoader extends ClassLoader {
+	static class JetConfigClassLoader extends URLClassLoader {
+
+		private static final Resource FALLBACK = new ClassPathResource("hazelcast.yaml");
 
 		JetConfigClassLoader() {
-			super(JetConfigClassLoader.class.getClassLoader());
+			super(new URL[0], JetConfigClassLoader.class.getClassLoader());
 		}
 
-		@Nullable
 		@Override
 		public URL getResource(String name) {
 			if (name.equals("hazelcast-jet-default.yaml")) {
-				try {
-					return new URL("file://hazelcast-jet-default.yaml");
-				}
-				catch (MalformedURLException ignored) {
-				}
+				return getEmulatedJestConfigUrl();
 			}
 			return super.getResource(name);
 		}
 
+		private URL getEmulatedJestConfigUrl() {
+			try {
+				return FALLBACK.getURL();
+			}
+			catch (IOException ex) {
+				throw new IllegalArgumentException(ex);
+			}
+		}
+
 	}
 
 }