Introduce the abstract MembershipEvent class to encapsulate the details of a membership event (e.g. memberJoined event) as defined by the o.a.g.distributed.internal.MembershipListener interface.

apache-geode-extensions/src/test/java/org/springframework/geode/distributed/event/MembershipEventUnitTests.java

@@ -0,0 +1,130 @@
+/*
+ * 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.distributed.event;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+
+import org.junit.Test;
+
+import org.apache.geode.distributed.DistributedMember;
+import org.apache.geode.distributed.internal.DistributionManager;
+import org.apache.geode.distributed.internal.InternalDistributedSystem;
+import org.apache.geode.internal.cache.InternalCache;
+
+/**
+ * Unit Tests for {@link MembershipEvent}.
+ *
+ * @author John Blum
+ * @see org.junit.Test
+ * @see org.mockito.Mockito
+ * @see org.apache.geode.distributed.DistributedMember
+ * @see org.apache.geode.distributed.DistributedSystem
+ * @see org.apache.geode.distributed.internal.DistributionManager
+ * @see org.springframework.geode.distributed.event.MembershipEvent
+ * @since 1.3.0
+ */
+public class MembershipEventUnitTests {
+
+	@Test
+	public void assertNotNullWithNonNullValue() {
+		assertThat(MembershipEvent.assertNotNull("test", "message")).isEqualTo("test");
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void assertNotNullWithNullValue() {
+
+		try {
+			MembershipEvent.assertNotNull(null, "Message with argument [%s]", "test");
+		}
+		catch (IllegalArgumentException expected) {
+
+			assertThat(expected).hasMessage("Message with argument [test]");
+			assertThat(expected).hasNoCause();
+
+			throw expected;
+		}
+	}
+
+	@Test
+	public void constructsNewMembershipEventWithDistributionManager() {
+
+		DistributionManager mockDistributionManager = mock(DistributionManager.class);
+
+		InternalCache mockCache = mock(InternalCache.class);
+
+		InternalDistributedSystem mockDistributedSystem = mock(InternalDistributedSystem.class);
+
+		doReturn(mockCache).when(mockDistributionManager).getCache();
+		doReturn(mockDistributedSystem).when(mockDistributionManager).getSystem();
+
+		MembershipEvent<TestMembershipEvent> event = new TestMembershipEvent(mockDistributionManager);
+
+		assertThat(event).isNotNull();
+		assertThat(event.getCache().orElse(null)).isEqualTo(mockCache);
+		assertThat(event.getDistributedMember().orElse(null)).isNull();
+		assertThat(event.getDistributedSystem().orElse(null)).isEqualTo(mockDistributedSystem);
+		assertThat(event.getDistributionManager()).isEqualTo(mockDistributionManager);
+		assertThat(event.getType()).isEqualTo(MembershipEvent.Type.UNQUALIFIED);
+
+		verify(mockDistributionManager, times(1)).getCache();
+		verify(mockDistributionManager, times(1)).getSystem();
+		verifyNoMoreInteractions(mockDistributionManager);
+	}
+
+	@Test
+	public void withMemberReturnsMember() {
+
+		DistributedMember mockDistributedMember = mock(DistributedMember.class);
+
+		DistributionManager mockDistributionManager = mock(DistributionManager.class);
+
+		MembershipEvent<TestMembershipEvent> event = new TestMembershipEvent(mockDistributionManager);
+
+		assertThat(event).isNotNull();
+		assertThat(event.getDistributedMember().orElse(null)).isNull();
+		assertThat(event.withMember(mockDistributedMember)).isSameAs(event);
+		assertThat(event.getDistributedMember().orElse(null)).isEqualTo(mockDistributedMember);
+		assertThat(event.withMember(null)).isSameAs(event);
+		assertThat(event.getDistributedMember().orElse(null)).isNull();
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void constructWithNullDistributionManagerThrowsIllegalArgumentException() {
+
+		try {
+			new TestMembershipEvent(null);
+		}
+		catch (IllegalArgumentException expected) {
+
+			assertThat(expected).hasMessage("DistributionManager must not be null");
+			assertThat(expected).hasNoCause();
+
+			throw expected;
+		}
+	}
+
+	static class TestMembershipEvent extends MembershipEvent<TestMembershipEvent> {
+
+		TestMembershipEvent(DistributionManager distributionManager) {
+			super(distributionManager);
+		}
+	}
+}