Add @AfterClass test logic to cleanup non-Standard Spring container Environment PropertySources if available.

spring-data-geode-test/src/test/java/org/springframework/data/gemfire/tests/integration/SpringEnvironmentPropertySourcesCleanupIntegrationTests.java

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+/*
+ *  Copyright 2019 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.data.gemfire.tests.integration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.data.gemfire.util.RuntimeExceptionFactory.newIllegalStateException;
+
+import java.util.Optional;
+import java.util.concurrent.atomic.AtomicReference;
+
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.junit.rules.ExternalResource;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.PropertySources;
+import org.springframework.lang.NonNull;
+import org.springframework.mock.env.MockPropertySource;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringRunner;
+
+/**
+ * Integration Tests testing and asserting the cleanup of the Spring container {@link ConfigurableEnvironment}
+ * and {@link PropertySources} linked to Unit & Integration testing.
+ *
+ * @author John Blum
+ * @see org.springframework.context.ConfigurableApplicationContext
+ * @see org.springframework.context.annotation.Configuration
+ * @see org.springframework.core.env.ConfigurableEnvironment
+ * @see org.springframework.core.env.PropertySources
+ * @see org.springframework.mock.env.MockPropertySource
+ * @see org.springframework.test.context.ContextConfiguration
+ * @see org.springframework.test.context.junit4.SpringRunner
+ * @since 0.0.24
+ */
+@RunWith(SpringRunner.class)
+@ContextConfiguration
+@SuppressWarnings("unused")
+public class SpringEnvironmentPropertySourcesCleanupIntegrationTests extends IntegrationTestsSupport {
+
+	private static final AtomicReference<ConfigurableApplicationContext> applicationContextReference =
+		new AtomicReference<>(null);
+
+	private static final String MOCK_PROPERTY_SOURCE_NAME = "MockPropertySource";
+
+	@ClassRule
+	public static final ExternalResource SPRING_ENVIRONMENT_RESOURCE_CLEANUP = new ExternalResource() {
+
+		@Override
+		protected void after() {
+
+			super.after();
+
+			Optional.ofNullable(applicationContextReference.get())
+				.map(ConfigurableApplicationContext::getEnvironment)
+				.map(ConfigurableEnvironment::getPropertySources)
+				.filter(propertySources -> Boolean.FALSE.equals(propertySources.contains(MOCK_PROPERTY_SOURCE_NAME)))
+				//.map(success -> { System.err.println("SUCCESS!"); return success; })
+				.orElseThrow(() -> newIllegalStateException(String.format(
+					"Spring Environment should not contain the [%s] PropertySource", MOCK_PROPERTY_SOURCE_NAME)));
+		}
+	};
+
+	@Autowired
+	private ConfigurableApplicationContext applicationContext;
+
+	@Before
+	public void setup() {
+
+		assertThat(this.applicationContext).isNotNull();
+		assertThat(this.applicationContext.isActive()).isTrue();
+
+		applicationContextReference.set(this.applicationContext);
+	}
+
+	@Test
+	public void applicationContextEnvironmentContainsMockPropertySource() {
+
+		ConfigurableEnvironment environment = this.applicationContext.getEnvironment();
+
+		assertThat(environment).isNotNull();
+
+		PropertySources propertySources = environment.getPropertySources();
+
+		assertThat(propertySources).isNotNull();
+		assertThat(propertySources.contains(MOCK_PROPERTY_SOURCE_NAME)).isTrue();
+	}
+
+	@Configuration
+	static class TestConfiguration {
+
+		@EventListener(classes = ContextRefreshedEvent.class)
+		public void addTestPropertySource(@NonNull ContextRefreshedEvent event) {
+
+			Optional.ofNullable(event)
+				.map(ContextRefreshedEvent::getApplicationContext)
+				.filter(ConfigurableApplicationContext.class::isInstance)
+				.map(ConfigurableApplicationContext.class::cast)
+				.map(ConfigurableApplicationContext::getEnvironment)
+				.map(ConfigurableEnvironment::getPropertySources)
+				.ifPresent(propertySources -> {
+
+					MockPropertySource mockPropertySource = new MockPropertySource("MockPropertySource");
+
+					propertySources.addLast(mockPropertySource);
+				});
+		}
+	}
+}