SpringCloud Alibaba Seata：ERROR io.seata.core.rpc.netty.NettyClientChannelManager - Failed to get available servers: 
2022-01-12 13:45:05.333 [timeoutChecker_1] ERROR io.seata.core.rpc.netty.NettyClientChannelManager - Failed to get available servers: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@2c88b9fc has been closed already
java.lang.IllegalStateException: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@2c88b9fc has been closed already
    at org.springframework.context.support.AbstractApplicationContext.assertBeanFactoryActive(AbstractApplicationContext.java:1092)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1125)
    at io.seata.spring.boot.autoconfigure.util.SpringUtils.getBean(SpringUtils.java:56)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider.get(SpringBootConfigurationProvider.java:106)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider.access$100(SpringBootConfigurationProvider.java:59)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider$1.intercept(SpringBootConfigurationProvider.java:72)
    at io.seata.config.FileConfiguration $$EnhancerByCGLIB$$ 862af1eb.getConfig()
    at io.seata.discovery.registry.RegistryFactory.getInstance(RegistryFactory.java:43)
    at io.seata.core.rpc.netty.NettyClientChannelManager.getAvailServerList(NettyClientChannelManager.java:216)
    at io.seata.core.rpc.netty.NettyClientChannelManager.reconnect(NettyClientChannelManager.java:162)
    at io.seata.core.rpc.netty.AbstractRpcRemotingClient$1.run(AbstractRpcRemotingClient.java:112)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
    at java.lang.Thread.run(Thread.java:748)
2022-01-12 13:45:05.371 [timeoutChecker_2] ERROR io.seata.core.rpc.netty.NettyClientChannelManager - Failed to get available servers: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@2c88b9fc has been closed already
java.lang.IllegalStateException: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@2c88b9fc has been closed already
    at org.springframework.context.support.AbstractApplicationContext.assertBeanFactoryActive(AbstractApplicationContext.java:1092)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1125)
    at io.seata.spring.boot.autoconfigure.util.SpringUtils.getBean(SpringUtils.java:56)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider.get(SpringBootConfigurationProvider.java:106)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider.access$100(SpringBootConfigurationProvider.java:59)
    at io.seata.spring.boot.autoconfigure.provider.SpringBootConfigurationProvider$1.intercept(SpringBootConfigurationProvider.java:72)
    at io.seata.config.FileConfiguration $$EnhancerByCGLIB$$ 862af1eb.getConfig()
    at io.seata.discovery.registry.RegistryFactory.getInstance(RegistryFactory.java:43)
    at io.seata.core.rpc.netty.NettyClientChannelManager.getAvailServerList(NettyClientChannelManager.java:216)
    at io.seata.core.rpc.netty.NettyClientChannelManager.reconnect(NettyClientChannelManager.java:162)
    at io.seata.core.rpc.netty.AbstractRpcRemotingClient$1.run(AbstractRpcRemotingClient.java:112)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
    at java.lang.Thread.run(Thread.java:748)

解决：
Seata服务闪退。