Caused by: java.lang.IllegalStateException: duplicate key: datasource

java.lang.IllegalStateException: Failed to load property source from location 'classpath:/application.yaml'
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:537)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadForFileExtension(ConfigFileApplicationListener.java:496)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:464)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$null$6(ConfigFileApplicationListener.java:446)
    at java.lang.Iterable.forEach(Iterable.java:75)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$load$7(ConfigFileApplicationListener.java:445)
    at java.lang.Iterable.forEach(Iterable.java:75)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:442)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:330)
    at org.springframework.boot.context.config.ConfigFileApplicationListener.addPropertySources(ConfigFileApplicationListener.java:212)
    at org.springframework.boot.context.config.ConfigFileApplicationListener.postProcessEnvironment(ConfigFileApplicationListener.java:195)
    at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:182)
    at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:168)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
    at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:74)
    at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
    at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:358)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:317)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243)
    at com.qingmu.MySpringBootSstart.main(MySpringBootSstart.java:16)
Caused by: java.lang.IllegalStateException: duplicate key: datasource
    at org.yaml.snakeyaml.constructor.SafeConstructor.processDuplicateKeys(SafeConstructor.java:99)
    at org.yaml.snakeyaml.constructor.SafeConstructor.flattenMapping(SafeConstructor.java:70)
    at org.yaml.snakeyaml.constructor.SafeConstructor.constructMapping2ndStep(SafeConstructor.java:182)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructMapping(BaseConstructor.java:443)
    at org.yaml.snakeyaml.constructor.SafeConstructor$ConstructYamlMap.construct(SafeConstructor.java:519)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructObjectNoCheck(BaseConstructor.java:207)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructObject(BaseConstructor.java:196)
    at org.springframework.boot.env.OriginTrackedYamlLoader$OriginTrackingConstructor.constructObject(OriginTrackedYamlLoader.java:94)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructMapping2ndStep(BaseConstructor.java:462)
    at org.yaml.snakeyaml.constructor.SafeConstructor.constructMapping2ndStep(SafeConstructor.java:183)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructMapping(BaseConstructor.java:443)
    at org.yaml.snakeyaml.constructor.SafeConstructor$ConstructYamlMap.construct(SafeConstructor.java:519)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructObjectNoCheck(BaseConstructor.java:207)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructObject(BaseConstructor.java:196)
    at org.springframework.boot.env.OriginTrackedYamlLoader$OriginTrackingConstructor.constructObject(OriginTrackedYamlLoader.java:94)
    at org.yaml.snakeyaml.constructor.BaseConstructor.constructDocument(BaseConstructor.java:161)
    at org.yaml.snakeyaml.constructor.BaseConstructor.getData(BaseConstructor.java:127)
    at org.yaml.snakeyaml.Yaml$1.next(Yaml.java:547)
    at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:168)
    at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:141)
    at org.springframework.boot.env.OriginTrackedYamlLoader.load(OriginTrackedYamlLoader.java:75)
    at org.springframework.boot.env.YamlPropertySourceLoader.load(YamlPropertySourceLoader.java:50)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadDocuments(ConfigFileApplicationListener.java:547)
    at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:517)
    ... 23 common frames omitted

因为我在使用的是yaml文件模式,然后因为:

去掉三个相同的键以后,就能够正常运行了.