我的项目具有此要求,即用户将CSV文件放置在必须推送到SQL Server数据库的共享位置。我碰到的所有教程都只使用带有硬编码CSV文件的内存数据库,如下所示
https://github.com/TechPrimers/spring-batch-example-1
通过对资源路径进行一些更改,我能够成功运行该应用程序以将CSV加载到DB中。
http://localhost:8081/load-Spring Batch的触发点。
http://localhost:8081/h2-console-用于查询内存表的H2控制台。
关于如何按照我们的要求进行此操作,我有几个一般性问题:
据我所知,内存中的DataSource
将自动配置为类似于以下内容: org.hibernate.dialect.H2Dialect
的意义是什么?
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
替换为以下sql server配置:
spring.datasource.url=jdbc:sqlserver://localhost;databaseName=springbootdb
spring.datasource.username=sa
spring.datasource.password=Projects@123
spring.datasource.driverClassName=com.microsoft.sqlserver.jdbc.SQLServerDriver
使用SQL Server替换了H2数据库jar:com.microsoft.sqlserver mssql-jdbc
6.1.0.jre8
test
从内存中切换到其他数据源(SQL Server)时,我不确定JPA的重要性吗?这是我们将其DataSource
从内存中的DB更改为SQL Server时遇到的错误,在此提供帮助。
Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2018-09-02 23:25:50.822 ERROR 6360 --- [ restartedMain] o.s.boot.SpringApplication : Application startup failed
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'inMemoryDatabaseShutdownExecutor' defined in class path resource [org/springframework/boot/devtools/autoconfigure/DevToolsDataSourceAutoConfiguration.class]: Unsatisfied dependency expressed through method 'inMemoryDatabaseShutdownExecutor' 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 java.lang.IllegalStateException: Cannot load driver class: com.microsoft.sqlserver.jdbc.SQLServerDriver
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:749) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:467) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1181) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1075) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:297) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1080) ~[spring-context-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:857) ~[spring-context-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) [spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) [spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) [spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) [spring-boot-1.5.14.RELEASE.jar:1.5.14.RELEASE]
at com.techprimers.springbatchexample1.SpringBatchExample1Application.main(SpringBatchExample1Application.java:10) [classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_151]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_151]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_151]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_151]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-1.5.14.RELEASE.jar:1.5.14.RELEASE]
Caused by: 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 java.lang.IllegalStateException: Cannot load driver class: com.microsoft.sqlserver.jdbc.SQLServerDriver
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1181) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1075) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
... 26 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.microsoft.sqlserver.jdbc.SQLServerDriver
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588) ~[spring-beans-4.3.18.RELEASE.jar:4.3.18.RELEASE]
... 39 common frames omitted
Caused by: java.lang.IllegalStateException: Cannot load driver class: com.microsoft.sqlserver.jdbc.SQLServerDriver
答案 0 :(得分:2)
org.hibernate.dialect.H2Dialect
的意义是什么?
像Hibernate这样的JPA实现需要生成SQL。
此SQL的详细信息取决于数据库。
Dialect
封装了这些差异。
因此,指定org.hibernate.dialect.H2Dialect
会告诉Hibernate生成适用于H2数据库的SQL。
这应该与您当前的问题无关。
关于您遇到的例外情况
该异常的根本原因是:
java.lang.IllegalStateException: Cannot load driver class: com.microsoft.sqlserver.jdbc.SQLServerDriver
这很可能意味着所提到的类不在类路径上。
您描述了您正在使用的依赖项
com.microsoft.sqlserver mssql-jdbc 6.1.0.jre8 test
我认为这应该意味着您的pom.xml
中的代码段
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<version>6.1.0.jre8</version>
<scope>test</scope>
</dependency>
如果是这种情况,则仅将驱动程序添加到测试范围。
即它仅可用于测试。
但是您似乎尝试实际启动应用程序,而不仅仅是运行一些测试。
因此,删除行<scope>test</scope>
应该可以解决此问题。
答案 1 :(得分:1)
您是否在pom.xml
中添加了以下依赖项
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>sqljdbc4</artifactId>
<version>4.0</version>
</dependency>
有关更多信息,请参考:https://springframework.guru/configuring-spring-boot-for-microsoft-sql-server/