java.lang.IllegalArgumentException: Param 'serviceName' is illegal, serviceName is blank
at com.alibaba.nacos.api.naming.utils.NamingUtils.getGroupedName(NamingUtils.java:47) ~[nacos-api-1.4.1.jar:na]
at com.alibaba.nacos.client.naming.NacosNamingService.subscribe(NacosNamingService.java:457) ~[nacos-client-1.4.1.jar:na]
at com.alibaba.cloud.nacos.discovery.NacosWatch.start(NacosWatch.java:123) ~[spring-cloud-starter-alibaba-nacos-discovery-2021.1.jar:2021.1]
at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) ~[spring-context-5.3.19.jar:5.3.19]
at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[na:na]
at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.19.jar:5.3.19]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.7.jar:2.6.7]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740) ~[spring-boot-2.6.7.jar:2.6.7]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415) ~[spring-boot-2.6.7.jar:2.6.7]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) ~[spring-boot-2.6.7.jar:2.6.7]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312) ~[spring-boot-2.6.7.jar:2.6.7]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) ~[spring-boot-2.6.7.jar:2.6.7]
at priv.lxg.cloud.NacosConfigClientMain3377.main(NacosConfigClientMain3377.java:15) ~[classes/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.6.7.jar:2.6.7]
解决办法：pom文件添加 bootstrap 依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-bootstrap</artifactId>
</dependency>