“应用程序无法启动”

Question

我收到以下异常：

2017-05-24 09:41:40.779  INFO 4412 --- [           main] com.develop.NewApplication               : Starting NewApplication on DESKTOP-4GP5JJA with PID 4412 (started by Athira S in C:\Users\Athira S\workspace\new)
2017-05-24 09:41:40.779  INFO 4412 --- [           main] com.develop.NewApplication               : No active profile set, falling back to default profiles: default
2017-05-24 09:41:40.857  INFO 4412 --- [           main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@6a28ffa4: startup date [Wed May 24 09:41:40 EDT 2017]; root of context hierarchy
2017-05-24 09:41:41.886  INFO 4412 --- [           main] f.a.AutowiredAnnotationBeanPostProcessor : JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
2017-05-24 09:41:42.198  WARN 4412 --- [           main] s.c.a.AnnotationConfigApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Cannot determine embedded database driver class for database type NONE. If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).
2017-05-24 09:41:42.214  INFO 4412 --- [           main] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-05-24 09:41:42.214 ERROR 4412 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

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

Description:

Cannot determine embedded database driver class for database type NONE

Action:

If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).

Answer 1

假设您正在处理 Spring Boot 应用程序，您有两种解决方案：

选项 1.如果您有一个可以连接到应用程序的数据库，请为 spring 数据源设置属性组：

示例 application.properties：

spring.datasource.url=jdbc://mysql://localhost:3306/dbname
spring.datasource.username=db_username
spring.datasource.password=db_password

（如果您正在使用，可以在 yml 中设置相同的属性组：）

示例应用程序.yml：

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/dbname
    username: db_username
    password: db_password

选项 2. 如果您没有要连接的数据库

删除对 spring-boot-starter-jdbc 的依赖 [或 spring-boot-starter-jpa 因为 jdbc starter 是 starter jpa 的依赖项]

如果您使用的是 maven，则该依赖项如下所示：

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

在 gradle 中，它会是这样的：

compile 'org.springframework.boot:spring-boot-starter-jdbc'

如果您不是这种情况，请添加更多上下文（例如您的 pom.xml | build.gradle 和/或 application.properties | application.yml，以便我们可以看到更多正在发生的事情。