Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient

FAILED: SemanticException org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient在进入hive时执行命令时报出如下错，特意记录下，再stackflow 上找到如下解决方法，亲测解决，原因应该是非正常关闭hive引起的。
starting the hive metastore service worked for me. First, set up the database for hive metastore:

$ hive --service metastore

` https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.3.4/bk_installing_manually_book/content/validate_installation.htmlSecond, run the following commands:

$ schematool -dbType mysql -initSchema
$ schematool -dbType mysql -info

https://cwiki.apache.org/confluence/display/Hive/Hive+Schema+Tool