From f4431aa71a15230c7eb9e7299ab47efad2b0c27e Mon Sep 17 00:00:00 2001
From: Anqi <anqi.wang@vesoft.com>
Date: Mon, 31 Oct 2022 14:46:50 +0800
Subject: [PATCH] update close() of connection pool to idempotent (#484)

---
 .../java/com/vesoft/nebula/client/graph/net/NebulaPool.java   | 4 +++-
 .../nebula/client/graph/net/RoundRobinLoadBalancer.java       | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
index 490b2081a..a1b3c8884 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/NebulaPool.java
@@ -124,7 +124,9 @@ public boolean init(List<HostAddress> addresses, NebulaPoolConfig config)
      * close the pool, all connections will be closed
      */
     public void close() {
-        checkClosed();
+        if (isClosed.get()) {
+            return;
+        }
         isClosed.set(true);
         this.loadBalancer.close();
         this.objectPool.close();
diff --git a/client/src/main/java/com/vesoft/nebula/client/graph/net/RoundRobinLoadBalancer.java b/client/src/main/java/com/vesoft/nebula/client/graph/net/RoundRobinLoadBalancer.java
index 1b3f3f3c2..e245141cf 100644
--- a/client/src/main/java/com/vesoft/nebula/client/graph/net/RoundRobinLoadBalancer.java
+++ b/client/src/main/java/com/vesoft/nebula/client/graph/net/RoundRobinLoadBalancer.java
@@ -48,7 +48,9 @@ public RoundRobinLoadBalancer(List<HostAddress> addresses, int timeout, SSLParam
     }
 
     public void close() {
-        schedule.shutdownNow();
+        if (!schedule.isShutdown()) {
+            schedule.shutdownNow();
+        }
     }
 
     @Override