sqlserverreader sqlserverwriter 数据同步时出现插件[null,null]加载失败问题

DataX (DATAX-OPENSOURCE-3.0), From Alibaba ! Copyright (C) 2010-2017, Alibaba Group. All Rights Reserved. 2019-02-14 14:25:00.481 [main] WARN ConfigParser - 插件[null,null]加载失败，1s后重试... Exception:Code:[Framework-12], Description:[DataX插件初始化错误, 该问题通常是由于DataX安装错误引起，请联系您的运维解决 .]. - 插件加载失败，未完成指定插件加载:[null] 2019-02-14 14:25:01.494 [main] ERROR Engine - 经DataX智能分析,该任务最可能的错误原因是: com.alibaba.datax.common.exception.DataXException: Code:[Framework-12], Description:[DataX插件初始化错误, 该问题通常是由于DataX安装错误引起，请联系您的运维解决 .]. - 插件加载失败，未完成指定插件加载:[null]

`{
"job": {
"setting": {
"speed": {
"byte": 1048576
}
},
"content": {
"reader": {
"name": "sqlserverreader",
"parameter": {
"username": "root",
"password": "root",
"column": "*",
"connection": {
"table": "t_aaaa",
"jdbcUrl": "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=test"

},
"querysql": "select FID, FApplyUserId from t_aaaa"
}
},
"writer": {
"name": "sqlserverwriter",
"parameter": {
"username": "root",
"password": "root",
"column": [
"FID", "FApplyUserId"
],
"connection": {
"table": "t_aaaa",
"jdbcUrl": "jdbc:sqlserver://127.0.0.1:1:1433;DatabaseName=testx"
},
"preSql": "delete from t_aaaa ;"
}
}
}

}
}`

请指教！！！

No source file or test is identified. Start by reproducing the failure with the supplied sqlserverreader/sqlserverwriter job configuration, then inspect DataX plugin discovery and initialization logs. Done means the cause of the null plugin names is identified and a verified configuration or installation fix is documented.

Written by the indexing model from the issue text.