详细报错：

 控制台直接往下拉，看后面：

到这里还在说废话，直接看 ### 的这几句就完了：

c.a.d.p.DruidPooledStatement - [errorCheck,370] - CommunicationsException, druid version 1.2.16, jdbcUrl : jdbc:mysql://10.27.30.33:36060/enterprise-man?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8, testWhileIdle true, idle millis 53279, minIdle 10, poolingCount 4, timeBetweenEvictionRunsMillis 60000, lastValidIdleMillis 53279, driver com.mysql.cj.jdbc.Driver, exceptionSorter com.alibaba.druid.pool.vendor.MySqlExceptionSorter 15:39:39.229 [http-nio-8080-exec-1] ERROR c.a.d.p.DruidDataSource - [handleFatalError,1954] - {conn-10005} discard

com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

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The last packet successfully received from the server was 53,271 milliseconds ago. The last packet sent successfully to the server was 53,282 milliseconds ago.

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### Error querying database.  Cause: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure     （发生错误的database）

The last packet successfully received from the server was 53,271 milliseconds ago. The last packet sent successfully to the server was 53,282 milliseconds ago.### The error may exist in file [C:\zhiZong\enterprise-man-service\enterpriseMan-service\target\classes\mapper\whjcxx\JcsbjcxxMapper.xml]   （发生错误的详细文件位置）### The error may involve   （发生错误的详细Mapper的SQL）com.ruoyi.enterpriseman.wh.mapper.JcsbjcxxMapper.selectJcsbjcxxListLimit-Inline### The error occurred while setting parameters （这个 错误 发生在 设置 参数 时）### SQL: SELECT * FROM xxx where  sblxmc = ?    LIMIT ?,?（发生错误的详细SQL打印）### Cause: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

其实如果是接口测试软件调取，一下子就可以看到报错点： 

 果不其然，是接参出异常了，修正即可

补充：

在parameterType即入参异常的情况下，也会出现这种情况