[DUBBO-3923] defensive check to solve issue #3923

[beiwei30]

What is the purpose of the change

defensive check to solve issue #3923

Brief changelog

XXXXX

Verifying this change

XXXXX

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[ralf0131]

LGTM.

[codecov-io]

Codecov Report

Merging #3931 into master will increase coverage by 0.01%.
The diff coverage is 0%.

@@             Coverage Diff              @@
##             master    #3931      +/-   ##
============================================
+ Coverage     63.66%   63.67%   +0.01%     
  Complexity       71       71              
============================================
  Files           713      713              
  Lines         31455    31459       +4     
  Branches       5070     5070              
============================================
+ Hits          20025    20032       +7     
+ Misses         9134     9133       -1     
+ Partials       2296     2294       -2

Impacted Files	Coverage Δ	Complexity Δ
...g/apache/dubbo/registry/consul/ConsulRegistry.java	0% <0%> (ø)	0 <0> (ø)	⬇️
.../apache/dubbo/remoting/transport/AbstractPeer.java	63.04% <0%> (-4.35%)	0% <0%> (ø)
...dubbo/remoting/exchange/support/DefaultFuture.java	72.78% <0%> (-2.05%)	0% <0%> (ø)
...pache/dubbo/registry/support/AbstractRegistry.java	78.92% <0%> (-1.54%)	0% <0%> (ø)
.../exchange/support/header/HeaderExchangeServer.java	66.98% <0%> (-0.95%)	0% <0%> (ø)
.../java/org/apache/dubbo/config/ReferenceConfig.java	60.51% <0%> (+0.36%)	0% <0%> (ø)	⬇️
...onfig/spring/extension/SpringExtensionFactory.java	80.48% <0%> (+2.43%)	0% <0%> (ø)	⬇️
...bo/rpc/cluster/support/FailbackClusterInvoker.java	70.49% <0%> (+3.27%)	0% <0%> (ø)	⬇️
...e/dubbo/remoting/transport/netty/NettyChannel.java	57.64% <0%> (+3.52%)	0% <0%> (ø)	⬇️
...ache/dubbo/remoting/p2p/support/AbstractGroup.java	56.81% <0%> (+11.36%)	0% <0%> (ø)	⬇️
... and 1 more

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