Spring Boot数独API启动失败：PostgreSQL驱动加载异常求助

我正在开发一个用于发送数独谜题的基础Spring Boot API，但启动时持续崩溃。这是我首次独立使用Spring框架，已遵循教程步骤操作，但问题仍未解决。

启动日志 #

2023-05-04T12:34:40.727-04:00  INFO 21276 --- [           main] com.sudoku.SudokuApplication             : Starting SudokuApplication using Java 17.0.6 with PID 21276 (C:\Users\olive\Downloads\sudokuApi\demo\target\classes started by olive in C:\Users\olive\Downloads\sudokuApi\demo)
2023-05-04T12:34:40.734-04:00  INFO 21276 --- [           main] com.sudoku.SudokuApplication             : No active profile set, falling back to 1 default profile: "default"
2023-05-04T12:34:42.424-04:00  INFO 21276 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2023-05-04T12:34:42.424-04:00  INFO 21276 --- [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.8]
2023-05-04T12:34:42.546-04:00  INFO 21276 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2023-05-04T12:34:42.658-04:00 ERROR 21276 --- [           main] com.zaxxer.hikari.HikariConfig           : Failed to load driver class org.postgresql.Driver from HikariConfig class classloader jdk.internal.loader.ClassLoaders$AppClassLoader@1d44bcfa
2023-05-04T12:34:42.666-04:00  INFO 21276 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2023-05-04T12:34:42.719-04:00 ERROR 21276 --- [           main] o.s.boot.SpringApplication               : Application run failed

application.properties配置 #

spring.main.banner-mode=off
logging.level.org.springframework=ERROR

spring.jpa.hibernate.ddl-auto=none

spring.datasource.initialization-mode=always
spring.datasource.platform=postgres
spring.datasource.url=jdbc:postgresql://localhost:5432/sudoku
spring.datasource.username=CHANGED
spring.datasource.password=CHANGED

spring.jpa.properties.hibernate.jdbc.lob.non_contextual_creation=true

pom.xml内容 #

<?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>3.0.6</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Sudoku</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

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

</project>

核心错误是Failed to load driver class org.postgresql.Driver，按以下步骤排查修复：

• 调整PostgreSQL依赖作用域
  pom.xml中PostgreSQL依赖的<scope>runtime</scope>可能导致启动时类加载失败，直接移除该scope，让依赖在编译和运行阶段都生效：

  <dependency>
      <groupId>org.postgresql</groupId>
      <artifactId>postgresql</artifactId>
  </dependency>
  

• 显式指定数据库驱动类
  在application.properties中添加驱动类配置，避免Spring自动探测出错：

  spring.datasource.driver-class-name=org.postgresql.Driver
  

• 确保依赖兼容并下载完整
  Spring Boot 3.0.x基于Jakarta EE，要求PostgreSQL驱动版本在42.5.x及以上，可显式指定版本：

  <dependency>
      <groupId>org.postgresql</groupId>
      <artifactId>postgresql</artifactId>
      <version>42.6.0</version>
  </dependency>
  

  执行mvn clean install刷新依赖，确认postgresql.jar已在本地仓库中。

• 验证数据库服务状态
  确认本地PostgreSQL服务已启动，端口5432正常开放，且数据库sudoku已提前创建。

内容的提问来源于stack exchange，提问作者Tablesalt