Spring Boot启动失败：无法配置DataSource，无法确定合适驱动类

错误日志 #

Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2022-12-27T22:34:33.521+05:30 ERROR 19798 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class


Action:

Consider the following:
    If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
    If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

我的application.yaml配置 #

#database config:mysql
spring.datasource.url=jdbc:mysql://localhost:3306/27Dec
spring.datasource.username=root
spring.datasource.password=mysql@17
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver



#hibernate config
spring.jpa.hibernate.ddl-auto = validate 
spring.jpa.show-sql = true
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL8Dialect


#when serilizing it wont restrict if fields are null or naything....
spring.jackson.serialization.fail-on-empty-beans=false 

spring.sql.init.platform=mysql
spring.sql.init.schema-locations=schema-mysql.sql
spring.sql.init.data-locations=data-mysql.sql
spring.datasource.initialize=true
spring.sql.init.continue-on-error=true

我的pom.xml配置 #

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://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>3.0.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.springrest</groupId>
    <artifactId>springrest</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springrest</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</java.version>
        <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version>
                <!-- use UTF-8 for everything -->
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
            <scope>provided</scope>
        </dependency> 
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
           <groupId>org.projectlombok</groupId>
           <artifactId>lombok</artifactId>
           <version>1.18.24</version>
           <scope>provided</scope>
       </dependency>
       <dependency>
    <groupId>javax.xml.bind</groupId>
    <artifactId>jaxb-api</artifactId>
    <version>2.3.0</version>
     </dependency>
     
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

已确认目标数据库及对应数据表已创建，试过Stack Overflow上的常规方案但无效，求解决该问题的思路。

解决思路 #

• 修复application.yaml格式错误：YAML格式要求用键: 值（冒号后加空格）的写法，而非等于号。正确配置示例：

  spring:
    datasource:
      url: jdbc:mysql://localhost:3306/27Dec
      username: root
      password: mysql@17
      driver-class-name: com.mysql.cj.jdbc.Driver
    jpa:
      hibernate:
        ddl-auto: validate
      show-sql: true
      properties:
        hibernate:
          dialect: org.hibernate.dialect.MySQL8Dialect
          naming:
            physical-strategy: org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl
    jackson:
      serialization:
        fail-on-empty-beans: false
    sql:
      init:
        platform: mysql
        schema-locations: schema-mysql.sql
        data-locations: data-mysql.sql
        continue-on-error: true
  

  注：spring.jpa.hibernate.naming-strategy在Spring Boot 2.x+已废弃，需改用physical-strategy或implicit-strategy。

• 修正JPA依赖的scope：spring-boot-starter-data-jpa的scope设为provided会导致运行时无法加载JPA核心类，移除该scope标签，使用默认的compile范围：

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

• 替换兼容的JAXB依赖：Spring Boot 3.0.x基于Jakarta EE API，原javax.xml.bind属于Java EE，需替换为Jakarta版本：

  <dependency>
      <groupId>jakarta.xml.bind</groupId>
      <artifactId>jakarta.xml.bind-api</artifactId>
      <version>4.0.0</version>
  </dependency>
  <dependency>
      <groupId>org.glassfish.jaxb</groupId>
      <artifactId>jaxb-runtime</artifactId>
      <version>4.0.0</version>
      <scope>runtime</scope>
  </dependency>
  

• 验证数据库连接可用性：确认MySQL服务正在运行，端口3306正常开放，用户名密码正确，数据库27Dec确实存在。

• 启用debug模式排查：启动应用时添加--debug参数，查看条件评估报告，确认数据源配置是否被正确加载。

内容的提问来源于stack exchange，提问作者Ritik Sharma