Add SimpleCacheResolver class to resolve instances of GemFire/Geode ClientCaches and peer Caches.

apache-geode-extensions/src/test/java/org/springframework/geode/cache/SimpleCacheResolverUnitTests.java

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+/*
+ * Copyright 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.geode.cache;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+
+/**
+ * Unit Tests for {@link SimpleCacheResolver}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.apache.geode.cache.Cache
+ * @see org.apache.geode.cache.GemFireCache
+ * @see org.apache.geode.cache.client.ClientCache
+ * @see org.springframework.geode.cache.SimpleCacheResolver
+ * @since 1.3.0
+ */
+public class SimpleCacheResolverUnitTests {
+
+	@Test
+	public void getInstanceReturnsASingleInstance() {
+
+		SimpleCacheResolver cacheResolver = SimpleCacheResolver.getInstance();
+
+		assertThat(cacheResolver).isNotNull();
+		assertThat(cacheResolver).isSameAs(SimpleCacheResolver.getInstance());
+	}
+
+	@Test
+	public void resolveWhenNoCacheIsPresentReturnsEmptyOptional() {
+		assertThat(SimpleCacheResolver.getInstance().resolve().orElse(null)).isNull();
+	}
+
+	@Test
+	public void resolveClientCacheWhenNoClientCacheIsPresentReturnsEmptyOptional() {
+		assertThat(SimpleCacheResolver.getInstance().resolveClientCache().orElse(null)).isNull();
+	}
+
+	@Test
+	public void resolvePeerCacheWhenNoPeerCacheIsPresentReturnsEmptyOptional() {
+		assertThat(SimpleCacheResolver.getInstance().resolvePeerCache().orElse(null)).isNull();
+	}
+
+	@Test(expected = IllegalStateException.class)
+	public void requireCacheWhenNoCacheIsPresentThrowsIllegalStateException() {
+
+		try {
+			SimpleCacheResolver.getInstance().require();
+		}
+		catch (IllegalStateException expected) {
+
+			assertThat(expected).hasMessage("GemFireCache not found");
+			assertThat(expected).hasNoCause();
+
+			throw expected;
+		}
+	}
+}

apache-geode-extensions/src/test/java/org/springframework/geode/cache/SimpleClientCacheResolverIntegrationTests.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 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.geode.cache;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Optional;
+
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.apache.geode.cache.client.ClientCache;
+import org.apache.geode.cache.client.ClientCacheFactory;
+
+/**
+ * Integration Tests for {@link SimpleCacheResolver} using a GemFire/Geode {@link ClientCache}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.apache.geode.cache.client.ClientCache
+ * @see org.apache.geode.cache.client.ClientCacheFactory
+ * @see org.springframework.geode.cache.SimpleCacheResolver
+ * @since 1.3.0
+ */
+public class SimpleClientCacheResolverIntegrationTests {
+
+	private static ClientCache clientCache;
+
+	@BeforeClass
+	public static void createClientCache() {
+		clientCache = new ClientCacheFactory().create();
+		assertThat(clientCache).isNotNull();
+	}
+
+	@AfterClass
+	public static void destroyClientCache() {
+		Optional.ofNullable(clientCache).ifPresent(ClientCache::close);
+		clientCache = null;
+	}
+
+	@Test
+	public void resolveReturnsClientCache() {
+		assertThat(SimpleCacheResolver.getInstance().resolve().orElse(null)).isSameAs(clientCache);
+	}
+
+	@Test
+	public void resolveClientCacheReturnsClientCache() {
+		assertThat(SimpleCacheResolver.getInstance().resolveClientCache().orElse(null)).isSameAs(clientCache);
+	}
+
+	@Test
+	public void resolvePeerCacheReturnsEmptyOptional() {
+		assertThat(SimpleCacheResolver.getInstance().resolvePeerCache().orElse(null)).isNull();
+	}
+
+	@Test
+	public void requireReturnsClientCache() {
+		assertThat(SimpleCacheResolver.getInstance().<ClientCache>require()).isSameAs(clientCache);
+	}
+}

apache-geode-extensions/src/test/java/org/springframework/geode/cache/SimplePeerCacheResolverIntegrationTests.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 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.geode.cache;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Optional;
+
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.apache.geode.cache.Cache;
+import org.apache.geode.cache.CacheFactory;
+
+/**
+ * Integration Tests for {@link SimpleCacheResolver} using a GemFire/Geode {@literal peer} {@link Cache}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.apache.geode.cache.Cache
+ * @see org.apache.geode.cache.CacheFactory
+ * @see org.springframework.geode.cache.SimpleCacheResolver
+ * @since 1.3.0
+ */
+public class SimplePeerCacheResolverIntegrationTests {
+
+	private static Cache peerCache;
+
+	@BeforeClass
+	public static void createPeerCache() {
+		peerCache = new CacheFactory().create();
+		assertThat(peerCache).isNotNull();
+	}
+
+	@AfterClass
+	public static void destroyPeerCache() {
+		Optional.ofNullable(peerCache).ifPresent(Cache::close);
+	}
+
+	@Test
+	public void resolveReturnsPeerCache() {
+		assertThat(SimpleCacheResolver.getInstance().resolve().orElse(null)).isSameAs(peerCache);
+	}
+
+	@Test
+	public void resolveClientCacheReturnsEmptyOptional() {
+		assertThat(SimpleCacheResolver.getInstance().resolveClientCache().orElse(null)).isNull();
+	}
+
+	@Test
+	public void resolvePeerCacheReturnsPeerCache() {
+		assertThat(SimpleCacheResolver.getInstance().resolvePeerCache().orElse(null)).isSameAs(peerCache);
+	}
+
+	@Test
+	public void requireReturnsPeerCache() {
+		assertThat(SimpleCacheResolver.getInstance().<Cache>require()).isSameAs(peerCache);
+	}
+}