fix jira 654 , after lc ,new leader heartbeat start failed

src/main/java/bftsmart/tom/core/Synchronizer.java

@@ -774,7 +774,7 @@ public class Synchronizer {
 		execManager.setNewLeader(electionResult.getRegency().getLeaderId());
 
 		// 重启心跳
-		tom.heartBeatTimer.restart();
+		tom.heartBeatTimer.restartformlc();
 		// 重启业务消息超时定时器
 		requestsTimer.startTimer(controller.getStaticConf().getRequestTimeout());
 

src/main/java/bftsmart/tom/leaderchange/HeartBeatTimer.java

@@ -102,6 +102,25 @@ public class HeartBeatTimer {
 		start();
 	}
 
+	// 在领导者切换过程中触发的心跳重新启动，要与领导者确认过程解耦
+	public synchronized void restartformlc() {
+		stopAll();
+		if (leaderTimer == null) {
+			leaderTimer = Executors.newSingleThreadScheduledExecutor();
+			leaderTimer.scheduleWithFixedDelay(new LeaderHeartbeatBroadcastingTask(this), NORMAL_DELAY,
+					tomLayer.controller.getStaticConf().getHeartBeatPeriod(), TimeUnit.MILLISECONDS);
+		}
+
+		if (followerTimer == null) {
+			// 非领导者心跳定时器重新开启后，更新上次心跳消息接收时间
+			heartBeatting.time = System.currentTimeMillis();
+			followerTimer = Executors.newSingleThreadScheduledExecutor();
+			followerTimer.scheduleWithFixedDelay(new FollowerHeartbeatCheckingTask(), NORMAL_DELAY,
+					tomLayer.controller.getStaticConf().getHeartBeatPeriod(), TimeUnit.MILLISECONDS);
+		}
+
+	}
+
 	public synchronized void stopAll() {
 		innerStop();
 	}