spring-boot 在非 Web 应用程序中创建非嵌入式数据源

Question

我正在尝试从 spring-boot 应用程序中使用 Grails GORM，并有一组与嵌入式数据库一起运行的测试。但是，我不能将代码移动到不同的数据库服务器（某些测试需要这样做。）

按照 (http://spring.io/guides/gs/accessing-data-gorm/) 的 Spring 指南，我在 src/main/resources/application.properties 中有以下内容：

spring.datasource.intialize=false
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://10.0.0.2/mydb? useLegacyDatetimeCode=false&serverTimezone=UTC
spring.datasource.username=user
spring.datasource.password=password

我有以下 gradle 依赖项，包括 Grails GORM 的项目：

dependencies {
  compile(
     "org.slf4j:slf4j-api:$slf4jVersion",
     "org.springframework.boot:spring-boot-starter-web",
     "org.springframework.boot:spring-boot-starter-jpa",
     "org.grails:gorm-hibernate4-spring-boot:1.0.0.RELEASE",
     "com.h2database:h2:$h2Version",
     "org.apache.tomcat:tomcat-jdbc:8.0.8"
  )

  runtime(
     "ch.qos.logback:logback-access:1.1.2",
     "ch.qos.logback:logback-classic:1.1.2",
     "mysql:mysql-connector-java:5.1.30")

  testCompile(
     "junit:junit",
     'org.spockframework:spock-core:0.7-groovy-2.0' )
}

运行测试并且日志包含Creating embedded database 'testdb'。无论我将属性更改为包含 spring.datasource.intialize=true 还是将依赖项更改为 spring-boot-starter-web（或两者兼而有之），情况仍然如此。

Spring Boot 的文档似乎暗示将属性添加到 application.properties 应该激活另一个数据库。 Spring boot did not create datasource 的答案似乎暗示确保 tomcat 和驱动程序在类路径上应该可以解决问题，但我已经检查了路径，并且 spring-boot-starter-web 和上述依赖项都在类路径上，这样似乎没有解决问题。

自动配置报告（有点长）如下。似乎报告找不到类 org.apache.tomcat.jdbc.pool.DataSource 。然而，它显示在我的 IDE 的类路径中，并且应该根据依赖项存在。

=========================
AUTO-CONFIGURATION REPORT
=========================


Positive matches:
-----------------

   MessageSourceAutoConfiguration
      - @ConditionalOnMissingBean (types: org.springframework.context.MessageSource; SearchStrategy: all) found no beans (OnBeanCondition)

   PropertyPlaceholderAutoConfiguration#propertySourcesPlaceholderConfigurer
      - @ConditionalOnMissingBean (types: org.springframework.context.support.PropertySourcesPlaceholderConfigurer; SearchStrategy: current) found no beans (OnBeanCondition)

   DataSourceAutoConfiguration
      - @ConditionalOnClass classes found: org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType (OnClassCondition)

   DataSourceAutoConfiguration.EmbeddedConfiguration
      - embedded database H2 detected (DataSourceAutoConfiguration.EmbeddedDatabaseCondition)
      - @ConditionalOnMissingBean (types: javax.sql.DataSource; SearchStrategy: all) found no beans (OnBeanCondition)

   DataSourceAutoConfiguration.JdbcTemplateConfiguration
      - existing auto database detected (DataSourceAutoConfiguration.DatabaseCondition)

   DataSourceAutoConfiguration.JdbcTemplateConfiguration#jdbcTemplate
      - @ConditionalOnMissingBean (types: org.springframework.jdbc.core.JdbcOperations; SearchStrategy: all) found no beans (OnBeanCondition)

   DataSourceAutoConfiguration.JdbcTemplateConfiguration#namedParameterJdbcTemplate
      - @ConditionalOnMissingBean (types: org.springframework.jdbc.core.namedparam.NamedParameterJdbcOperations; SearchStrategy: all) found no beans (OnBeanCondition)

   DataSourceTransactionManagerAutoConfiguration
      - @ConditionalOnClass classes found: org.springframework.jdbc.core.JdbcTemplate,org.springframework.transaction.PlatformTransactionManager (OnClassCondition)

   DataSourceTransactionManagerAutoConfiguration.TransactionManagementConfiguration
      - @ConditionalOnMissingBean (types: org.springframework.transaction.annotation.AbstractTransactionManagementConfiguration; SearchStrategy: all) found no beans (OnBeanCondition)

   JmxAutoConfiguration
      - @ConditionalOnClass classes found: org.springframework.jmx.export.MBeanExporter (OnClassCondition)
      - SpEL expression on org.springframework.boot.autoconfigure.jmx.JmxAutoConfiguration: ${spring.jmx.enabled:true} (OnExpressionCondition)
      - @ConditionalOnMissingBean (types: org.springframework.jmx.export.MBeanExporter; SearchStrategy: all) found no beans (OnBeanCondition)


Negative matches:
-----------------

   RabbitAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.amqp.rabbit.core.RabbitTemplate,com.rabbitmq.client.Channel (OnClassCondition)

   AopAutoConfiguration
      - required @ConditionalOnClass classes not found: org.aspectj.lang.annotation.Aspect,org.aspectj.lang.reflect.Advice (OnClassCondition)

   BatchAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.batch.core.launch.JobLauncher (OnClassCondition)

   JpaRepositoriesAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.data.jpa.repository.JpaRepository (OnClassCondition)

   MongoRepositoriesAutoConfiguration
      - required @ConditionalOnClass classes not found: com.mongodb.Mongo,org.springframework.data.mongodb.repository.MongoRepository (OnClassCondition)

   DataSourceAutoConfiguration.DbcpConfiguration
      - org.apache.commons.dbcp.BasicDataSource DataSource class not found (DataSourceAutoConfiguration.BasicDatabaseCondition)

   DataSourceAutoConfiguration.TomcatConfiguration
      - org.apache.tomcat.jdbc.pool.DataSource DataSource class not found (DataSourceAutoConfiguration.TomcatDatabaseCondition)

   DataSourceTransactionManagerAutoConfiguration#transactionManager
      - @ConditionalOnMissingBean (names: transactionManager; SearchStrategy: all) found the following [transactionManager] (OnBeanCondition)

   JmsTemplateAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.jms.core.JmsTemplate,javax.jms.ConnectionFactory (OnClassCondition)

   DeviceResolverAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.mobile.device.DeviceResolverHandlerInterceptor,org.springframework.mobile.device.DeviceHandlerMethodArgumentResolver (OnClassCondition)

   MongoAutoConfiguration
      - required @ConditionalOnClass classes not found: com.mongodb.Mongo (OnClassCondition)

   MongoTemplateAutoConfiguration
      - required @ConditionalOnClass classes not found: com.mongodb.Mongo,org.springframework.data.mongodb.core.MongoTemplate (OnClassCondition)

   HibernateJpaAutoConfiguration
      - did not find HibernateEntityManager class (HibernateJpaAutoConfiguration.HibernateEntityManagerCondition)

   ReactorAutoConfiguration
      - required @ConditionalOnClass classes not found: reactor.spring.context.config.EnableReactor (OnClassCondition)

   RedisAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.data.redis.connection.lettuce.LettuceConnection,org.springframework.data.redis.core.RedisOperations,com.lambdaworks.redis.RedisClient (OnClassCondition)

   FallbackWebSecurityAutoConfiguration
      - SpEL expression on org.springframework.boot.autoconfigure.security.FallbackWebSecurityAutoConfiguration: !${security.basic.enabled:true} (OnExpressionCondition)

   SecurityAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.security.authentication.AuthenticationManager (OnClassCondition)

   ThymeleafAutoConfiguration
      - required @ConditionalOnClass classes not found: org.thymeleaf.spring4.SpringTemplateEngine (OnClassCondition)

   DispatcherServletAutoConfiguration
      - web application classes not found (OnWebApplicationCondition)

   EmbeddedServletContainerAutoConfiguration
      - web application classes not found (OnWebApplicationCondition)

   HttpMessageConvertersAutoConfiguration
      - required @ConditionalOnClass classes not found: org.springframework.http.converter.HttpMessageConverter (OnClassCondition)

   MultipartAutoConfiguration
      - required @ConditionalOnClass classes not found: javax.servlet.Servlet,org.springframework.web.multipart.support.StandardServletMultipartResolver (OnClassCondition)

   ServerPropertiesAutoConfiguration
      - web application classes not found (OnWebApplicationCondition)

   WebMvcAutoConfiguration
      - web application classes not found (OnWebApplicationCondition)

   WebSocketAutoConfiguration
      - required @ConditionalOnClass classes not found: javax.servlet.Servlet,org.apache.catalina.startup.Tomcat,org.springframework.web.socket.WebSocketHandler,org.apache.tomcat.websocket.server.WsSci (OnClassCondition)

Answer 1

事实证明很难找到修复程序，但并不难。诀窍是在org.apache.tomcat:tomcat-jdbc: 的适当版本上添加运行时依赖项。对于 Java 6，我使用了 7.0.54。对于 Java 7 或 8，请使用 8.0.8。请注意，7. 系列并未在 Maven Central 上列为最新版本。

显然这个依赖不是由 web starter 引入的，所以必须添加。

找到这个的难点在于，如果类由于某种原因无法加载，例如不兼容的 JRE，它会默默地找不到它。我只是在尝试显式加载类时才发现这个问题。