创建springBoot项目及启动报错遇到的问题解决：Failed to configure a DataSource: 'url' attribute is not specified and no embedd

    ***************************  
    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).  

spring:
  application:
    name: openGauss Exam
  datasource:
    url: jdbc:postgresql://***
    driver-class-name: org.postgresql.Driver
    username: **
    password: ***
    hikari:
      login-timeout: 30
      connection-timeout: 10000
      idle-timeout: 600000
      max-lifetime: 1800000
      connection-test-query: select 1

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
public class ExamApplication {
    public static void main(String[] args) {
        SpringApplication.run(ExamApplication.class, args);
    }
}

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.springframework.cglib.core.ReflectUtils$1 (file:/C:/Users/%e5%85%b3%e6%96%87%e5%b3%b0/.m2/repository/org/springframework/spring-core/5.0.6.RELEASE/spring-core-5.0.6.RELEASE.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of org.springframework.cglib.core.ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

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