There's no need to null test in conjunction with an instanceof test. …

[liugddx]

…null is not an instanceof anything, so a null check is redundant.

What is the purpose of the change

There's no need to null test in conjunction with an instanceof test. null is not an instanceof anything, so a null check is redundant.

Brief changelog

There's no need to null test in conjunction with an instanceof test. null is not an instanceof anything, so a null check is redundant.

Verifying this change

XXXXX

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[ralf0131]

LGTM, thanks for the pull request!

[ralf0131]

Please merge it if All CI pass.

[kun-song]

Hi @ralf0131 , the CI seems not happy:

The command "~/bin/install-jdk.sh --target "/home/travis/openjdk11" --workspace "/home/travis/.cache/install-jdk" --feature "11" --license "GPL" --cacerts" failed and exited with 51 during .

Maybe a same problem to this Travis CI couldn't install openjdk11

[kun-song]

We already have a PR to fix it #3948