Introduce the MemberJoinedEvent class extending MembershipEvent to signal when a new member joins the distributed system (cluster) as a peer.

apache-geode-extensions/src/main/java/org/springframework/geode/distributed/event/support/MemberJoinedEvent.java

@@ -0,0 +1,54 @@
+/*
+ * 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.support;
+
+import org.apache.geode.distributed.DistributedMember;
+import org.apache.geode.distributed.DistributedSystem;
+import org.apache.geode.distributed.internal.DistributionManager;
+
+import org.springframework.geode.distributed.event.MembershipEvent;
+
+/**
+ * {@link MembershipEvent} fired when a {@link DistributedMember} joins the {@link DistributedSystem}.
+ *
+ * @author John Blum
+ * @see org.apache.geode.distributed.DistributedMember
+ * @see org.apache.geode.distributed.DistributedSystem
+ * @see org.springframework.geode.distributed.event.MembershipEvent
+ * @since 1.3.0
+ */
+public class MemberJoinedEvent extends MembershipEvent<MemberJoinedEvent> {
+
+	/**
+	 * Constructs a new instance of {@link MemberJoinedEvent} initialized with the given {@link DistributionManager}.
+	 *
+	 * @param distributionManager {@link DistributionManager} used as the {@link #getSource() source} of this event;
+	 * must not be {@literal null}.
+	 * @throws IllegalArgumentException if {@link DistributionManager} is {@literal null}.
+	 * @see org.apache.geode.distributed.internal.DistributionManager
+	 */
+	public MemberJoinedEvent(DistributionManager distributionManager) {
+		super(distributionManager);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	@Override
+	public Type getType() {
+		return Type.MEMBER_JOINED;
+	}
+}