SpringBoot添加application.yml后运行报错：classpath缺失snakeyaml依赖

错误信息 #

Exception in thread "main" java.lang.IllegalStateException: Attempted to load Config resource 'class path resource [application.yml]' via location 'optional:classpath:/' but snakeyaml was not found on the classpath
    at org.springframework.boot.env.YamlPropertySourceLoader.load(YamlPropertySourceLoader.java:47)
    at org.springframework.boot.context.config.StandardConfigDataLoader.load(StandardConfigDataLoader.java:54)
    at org.springframework.boot.context.config.StandardConfigDataLoader.load(StandardConfigDataLoader.java:36)
    at org.springframework.boot.context.config.ConfigDataLoaders.load(ConfigDataLoaders.java:107)
    at org.springframework.boot.context.config.ConfigDataImporter.load(ConfigDataImporter.java:128)
    at org.springframework.boot.context.config.ConfigDataImporter.resolveAndLoad(ConfigDataImporter.java:86)
    at org.springframework.boot.context.config.ConfigDataEnvironmentContributors.withProcessedImports(ConfigDataEnvironmentContributors.java:116)
    at org.springframework.boot.context.config.ConfigDataEnvironment.processInitial(ConfigDataEnvironment.java:240)
    at org.springframework.boot.context.config.ConfigDataEnvironment.processAndApply(ConfigDataEnvironment.java:227)
    at org.springframework.boot.context.config.ConfigDataEnvironmentPostProcessor.postProcessEnvironment(ConfigDataEnvironmentPostProcessor.java:102)
    at org.springframework.boot.context.config.ConfigDataEnvironmentPostProcessor.postProcessEnvironment(ConfigDataEnvironmentPostProcessor.java:94)
    at org.springframework.boot.env.EnvironmentPostProcessorApplicationListener.onApplicationEnvironmentPreparedEvent(EnvironmentPostProcessorApplicationListener.java:102)
    at org.springframework.boot.env.EnvironmentPostProcessorApplicationListener.onApplicationEvent(EnvironmentPostProcessorApplicationListener.java:87)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:131)
    at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:85)
    at org.springframework.boot.SpringApplicationRunListeners.lambda$environmentPrepared$2(SpringApplicationRunListeners.java:66)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:120)
    at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:114)
    at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:65)
    at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:339)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:297)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301)
    at com.voicebase.analyticys.MySpringbootMainClass.main(MySpringbootMainClass.java:12)
    at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
    at java.base/java.lang.reflect.Method.invoke(Method.java:577)
    at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:131)

问题描述 #

添加application.yml配置文件后，打包成jar运行时抛出上述错误；在IntelliJ中不使用该配置文件可正常运行。已检查配置文件缩进、确认target目录下存在application.yml，尝试过重新编写配置文件，问题仍未解决。

项目pom.xml #

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.6</version>
    </parent>

    <groupId>com.voicebase.analytics</groupId>
    <artifactId>test-vbmedia-tokinesis</artifactId>
    <version>0.1.0-SNAPSHOT</version>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
            <version>2.6.6</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.retry</groupId>
            <artifactId>spring-retry</artifactId>
            <version>1.3.2</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>5.3.18</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
        </dependency>
    </dependencies>
    <build>
        <plugins>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-enforcer-plugin</artifactId>
            </plugin>

            <plugin>
                <groupId>com.theoryinpractise</groupId>
                <artifactId>googleformatter-maven-plugin</artifactId>
            </plugin>

            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <executable>true</executable>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
            </plugin>

            <plugin>
                <!-- Build an executable JAR -->
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <!--                <version>3.1.0</version>-->
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>my.package.MainClassNameApp</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

解决方案 #

1. 补充snakeyaml依赖 #

SpringBoot解析YAML配置必须依赖snakeyaml库，你的pom中未引入该依赖。有两种方式添加：

• 直接引入snakeyaml：

<dependency>
    <groupId>org.yaml</groupId>
    <artifactId>snakeyaml</artifactId>
    <scope>compile</scope>
</dependency>

• 推荐替换为spring-boot-starter（自动包含snakeyaml及其他核心依赖）：
  将现有spring-boot-autoconfigure依赖替换为：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter</artifactId>
</dependency>

2. 清理重复的Maven插件 #

pom中重复声明了spring-boot-maven-plugin，合并为一个避免打包冲突：

<plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
    <configuration>
        <executable>true</executable>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>repackage</goal>
            </goals>
        </execution>
    </executions>
</plugin>

3. 重新打包运行 #

执行命令重新打包：

mvn clean package

然后运行生成的jar文件即可。

内容的提问来源于stack exchange，提问作者userdr725