具体警告如下：

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.apache.hadoop.security.authentication.util.KerberosUtil (file:/home/hadoop/hadoop-2.9.0/share/hadoop/common/lib/hadoop-auth-2.9.0.jar) to method sun.security.krb5.Config.getInstance()
WARNING: Please consider reporting this to the maintainers of org.apache.hadoop.security.authentication.util.KerberosUtil
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

不多说了，原因可能是 JDK 的原因，我用的 JDK9 ，换成 JDK8 问题解决…

fuck JDK9…

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