SpringBoot启动yaml报错
报错找不到org.yaml里的一个方法
10:45:54.742 [main] ERROR org.springframework.boot.SpringApplication - Application run failed
java.lang.NoSuchMethodError: org.yaml.snakeyaml.nodes.ScalarNode.getScalarStyle()Lorg/yaml/snakeyaml/DumperOptions$ScalarStyle;
at org.springframework.boot.env.OriginTrackedYamlLoader$KeyScalarNode.<init>(OriginTrackedYamlLoader.java:127)
at org.springframework.boot.env.OriginTrackedYamlLoader$KeyScalarNode.get(OriginTrackedYamlLoader.java:138)
at org.springframework.boot.env.OriginTrackedYamlLoader$KeyScalarNode.get(OriginTrackedYamlLoader.java:133)
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1384)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472)
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:566)
at org.springframework.boot.env.OriginTrackedYamlLoader$OriginTrackingConstructor.replaceMappingNodeKeys(OriginTrackedYamlLoader.java:99)
at org.springframework.boot.env.OriginTrackedYamlLoader$OriginTrackingConstructor.constructObject(OriginTrackedYamlLoader.java:92)
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$1.next(Yaml.java:547)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:160)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:134)
at org.springframework.boot.env.OriginTrackedYamlLoader.load(OriginTrackedYamlLoader.java:75)
at org.springframework.boot.env.YamlPropertySourceLoader.load(YamlPropertySourceLoader.java:50)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadDocuments(ConfigFileApplicationListener.java:574)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:528)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadForFileExtension(ConfigFileApplicationListener.java:502)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:469)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$null$6(ConfigFileApplicationListener.java:450)
at java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$load$7(ConfigFileApplicationListener.java:449)
at java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:446)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:334)
at org.springframework.boot.context.config.ConfigFileApplicationListener.addPropertySources(ConfigFileApplicationListener.java:209)
at org.springframework.boot.context.config.ConfigFileApplicationListener.postProcessEnvironment(ConfigFileApplicationListener.java:192)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:179)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:165)
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:75)
at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:347)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:306)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248)
解决
核对了下引入的包，发现项目中额外引入了1.19版本的org.yaml.snakeyaml包，这个包里确实没有这个方法。把这个包改成1.26的即可。
SpringBoot配置文件application.yml遇到的坑
1.第一个坑
原代码：
username:root
password:123456项目启动报以下异常：
Caused by: org.yaml.snakeyaml.scanner.ScannerException: while scanning a simple key
产生问题的根源：application.yml文件键、值对之间要用冒号：隔开，而且冒号和值之间有一个空格
上述异常产生的就是键后面的：号紧接着写值，没有留一个空格。
解决办法：
冒号：后面留出一个空格后再写值
2.第二个坑
原代码参见下图：
项目启动以后报以下异常：
Caused by: org.yaml.snakeyaml.scanner.ScannerException: mapping values are not allowed here
或
Caused by: org.yaml.snakeyaml.parser.ParserException: while parsing a block mapping
expected <block end>, but found '<block mapping start>'
in 'reader', line 11, column 3:
jpa:
产生问题的根源：application.yml一级键，空一格写就可以了。像Jpa这样是一级键，下属的database是二级键。
解决办法：
Jpa向左前进一格到中间箭头的方位即可。
以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程网。
