After creating springbootdemo, run the command to report the MongoSocketOpenException error solution,

After creating springbootdemo, run the command to report the MongoSocketOpenException error solution,

On the SpringbootdemoApplication class, right-click Run as and select Spring Boot App. Then, the Console outputs the following error log:

Com. mongodb. MongoSocketOpenException: Exception opening socket
At com. mongodb. connection. SocketStream. open (SocketStream. java: 63 )~ [Mongodb-driver-core-3.4.2.jar: na]
At com. mongodb. connection. InternalStreamConnection. open (InternalStreamConnection. java: 115 )~ [Mongodb-driver-core-3.4.2.jar: na]
At com. mongodb. connection. DefaultServerMonitor $ ServerMonitorRunnable. run (DefaultServerMonitor. java: 113 )~ [Mongodb-driver-core-3.4.2.jar: na]
At java. lang. Thread. run (Unknown Source) [na: 1.8.0 _ 91]
Caused by: java.net. ConnectException: Connection refused: connect
At java.net. DualStackPlainSocketImpl. waitForConnect (Native Method )~ [Na: 1.8.0 _ 91]
At java.net. DualStackPlainSocketImpl. socketConnect (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. AbstractPlainSocketImpl. doConnect (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. AbstractPlainSocketImpl. connectToAddress (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. AbstractPlainSocketImpl. connect (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. PlainSocketImpl. connect (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. SocksSocketImpl. connect (Unknown Source )~ [Na: 1.8.0 _ 91]
At java.net. Socket. connect (Unknown Source )~ [Na: 1.8.0 _ 91]
At com. mongodb. connection. SocketStreamHelper. initialize (SocketStreamHelper. java: 57 )~ [Mongodb-driver-core-3.4.2.jar: na]
At com. mongodb. connection. SocketStream. open (SocketStream. java: 58 )~ [Mongodb-driver-core-3.4.2.jar: na]
... 3 common frames omitted

Go to Baidu and find an article stating that springboot is automatically configured to support mongodb. A mongo instance is automatically instantiated when spring boot is started. You need to disable automatic configuration,

Add@ SpringBootApplication (exclude = export autoconfiguration. class)The original Article is http://blog.csdn.net/xuyw#/article/details/72918360.

After I add annotations to the class, this error is solved, but a new error log is output, as shown below:

Java. lang. ClassCastException: org. springframework. boot. context. event. ApplicationFailedEvent cannot be cast to org. springframework. boot. web. context. WebServerInitializedEvent
At org. springframework. context. event. SimpleApplicationEventMulticaster. invokeListener (SimpleApplicationEventMulticaster. java: 159) [spring-context-5.0.0.RC3.jar: 5.0.0.RC3]
At org. springframework. context. event. SimpleApplicationEventMulticaster. multicastEvent (SimpleApplicationEventMulticaster. java: 139) [spring-context-5.0.0.RC3.jar: 5.0.0.RC3]
At org. springframework. context. event. SimpleApplicationEventMulticaster. multicastEvent (SimpleApplicationEventMulticaster. java: 127) [spring-context-5.0.0.RC3.jar: 5.0.0.RC3]
At org. springframework. boot. context. event. EventPublishingRunListener. finished (EventPublishingRunListener. java: 114) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplicationRunListeners. callFinishedListener (SpringApplicationRunListeners. java: 79) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplicationRunListeners. finished (SpringApplicationRunListeners. java: 72) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplication. handleRunFailure (SpringApplication. java: 803) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplication. run (SpringApplication. java: 338) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplication. run (SpringApplication. java: 1245) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At org. springframework. boot. SpringApplication. run (SpringApplication. java: 1233) [spring-boot-2.0.0.M3.jar: 2.0.0.M3]
At com. example. demo. SpringbootdemoApplication. main (SpringbootdemoApplication. java: 22) [classes/: na],

Copy the first line of Error Log and search for the answer on Google. You need to comment out the Mongo-related startup statement in the pom. xml file of the project, as shown below:

<! -- <Dependency>
<GroupId> org. springframework. boot </groupId>
<ArtifactId> spring-boot-starter-data-mongodb </artifactId>
</Dependency> -->

Save and restart. No error is reported. Link to the original github article: https://github.com/spring-projects/spring-boot/issues/10047.