java - 在 Spring 宠物诊所切换数据库

Question

我试图在 the spring petclinic sample application 中从 hsql 切换到 MySQL .有人可以告诉我我做错了什么吗？

我按照 petclinic_db_setup_mysql.txt 文件中的说明进行操作，并确认数据库已在 mysql 中正确创建，但是当我尝试从 eclipse 中在 tomcat 7 上运行应用程序时出现以下错误:

org.springframework.beans.factory.BeanDefinitionStoreException:  
Invalid bean definition with name 'entityManagerFactory' defined in class path resource  
[spring/business-config.xml]:  
Could not resolve placeholder 'jpa.showSql' in string value "${jpa.showSql}"

这是业务配置中的相关代码:

   <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
          p:dataSource-ref="dataSource">
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"
                  p:database="${jpa.database}" p:showSql="${jpa.showSql}"/>
            <!-- the 'database' parameter refers to the database dialect being used.
                By default, Hibernate will use a 'HSQL' dialect because 'jpa.database' has been set to 'HSQL'
                inside file spring/data-access.properties
             -->
        </property>
        <!-- gDickens: BOTH Persistence Unit and Packages to Scan are NOT compatible, persistenceUnit will win -->
        <property name="persistenceUnitName" value="petclinic"/>
        <property name="packagesToScan" value="org.springframework.samples.petclinic"/>
    </bean>

这里是 data-access.properties 的内容:

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/petclinic
jdbc.username=root
jdbc.password=some_pwd

# Properties that control the population of schema and data for a new data source
jdbc.initLocation=classpath:db/mysql/initDB.sql
jdbc.dataLocation=classpath:db/mysql/populateDB.sql

# Property that determines which Hibernate dialect to use
# (only applied with "applicationContext-hibernate.xml")
hibernate.dialect=org.hibernate.dialect.MySQLDialect

# Property that determines which database to use with an AbstractJpaVendorAdapter
jpa.database=MYSQL
jpa.showSql = true #Added at Dan's suggestion, but new error occurs now.  

---

编辑:

我如上所示添加了 jpa.showSql=true，但现在抛出以下新错误消息:

ERROR ContextLoader - Context initialization failed
org.springframework.beans.factory.BeanCreationException:  
Error creating bean with name 'org.springframework.jdbc.datasource.init.DataSourceInitializer#0':  
Invocation of init method failed; nested exception is org.springframework.dao.DataAccessResourceFailureException:  
Failed to execute database script; nested exception is org.springframework.jdbc.CannotGetJdbcConnectionException:  
Could not get JDBC Connection;  
nested exception is java.sql.SQLException: com.mysql.jdbc.Driver

我确认数据库密码是正确的(不是上面的假密码)，我可以在 MySQL 命令行客户端中浏览数据库。所以问题在于将 Web 应用程序连接到数据库。有人有进一步的建议吗？

应 Sotirios 的要求，这里是同一错误的更完整的堆栈跟踪:

Nov 28, 2013 1:51:31 PM org.apache.catalina.core.StandardContext listenerStart
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.jdbc.datasource.init.DataSourceInitializer#0': Invocation of init method failed; nested exception is org.springframework.dao.DataAccessResourceFailureException: Failed to execute database script; nested exception is org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1512)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:296)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:293)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:628)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:389)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:294)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
    at java.util.concurrent.FutureTask.run(FutureTask.java:138)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:662)
Caused by: org.springframework.dao.DataAccessResourceFailureException: Failed to execute database script; nested exception is org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute(DatabasePopulatorUtils.java:56)
    at org.springframework.jdbc.datasource.init.DataSourceInitializer.afterPropertiesSet(DataSourceInitializer.java:83)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1571)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1509)
    ... 22 more
Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80)
    at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute(DatabasePopulatorUtils.java:45)
    ... 25 more
Caused by: java.sql.SQLException: com.mysql.jdbc.Driver
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:702)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:634)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:488)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:144)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:116)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:103)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:127)
    at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
    ... 26 more
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:247)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:246)
    ... 36 more
Nov 28, 2013 1:51:31 PM org.apache.catalina.core.StandardContext startInternal
SEVERE: Error listenerStart
ERROR ContextLoader - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.jdbc.datasource.init.DataSourceInitializer#0': Invocation of init method failed; nested exception is org.springframework.dao.DataAccessResourceFailureException: Failed to execute database script; nested exception is org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1512) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:296) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:293) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:628) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932) ~[spring-context-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479) ~[spring-context-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:389) ~[spring-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:294) ~[spring-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112) [spring-web-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939) [catalina.jar:7.0.42]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) [catalina.jar:7.0.42]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) [catalina.jar:7.0.42]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559) [catalina.jar:7.0.42]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549) [catalina.jar:7.0.42]
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) [na:1.6.0_29]
    at java.util.concurrent.FutureTask.run(FutureTask.java:138) [na:1.6.0_29]
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [na:1.6.0_29]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [na:1.6.0_29]
    at java.lang.Thread.run(Thread.java:662) [na:1.6.0_29]
Caused by: org.springframework.dao.DataAccessResourceFailureException: Failed to execute database script; nested exception is org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute(DatabasePopulatorUtils.java:56) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.jdbc.datasource.init.DataSourceInitializer.afterPropertiesSet(DataSourceInitializer.java:83) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1571) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1509) ~[spring-beans-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    ... 22 common frames omitted
Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.jdbc.Driver
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute(DatabasePopulatorUtils.java:45) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    ... 25 common frames omitted
Caused by: java.sql.SQLException: com.mysql.jdbc.Driver
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:702) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:634) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:488) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:144) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:116) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:103) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:127) ~[tomcat-jdbc-7.0.42.jar:na]
    at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) ~[spring-jdbc-3.2.5.RELEASE.jar:3.2.5.RELEASE]
    ... 26 common frames omitted
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714) ~[catalina.jar:7.0.42]
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559) ~[catalina.jar:7.0.42]
    at java.lang.Class.forName0(Native Method) ~[na:1.6.0_29]
    at java.lang.Class.forName(Class.java:247) ~[na:1.6.0_29]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:246) ~[tomcat-jdbc-7.0.42.jar:na]
    ... 36 common frames omitted
Nov 28, 2013 1:51:31 PM org.apache.catalina.core.StandardContext startInternal
SEVERE: Context [/petclinic] startup failed due to previous errors

Answer 1

对于原始错误，see Dan's answer .当 Spring 发现无法解决的属性时，它会立即失败，因此在解决此问题之前它不会处理下一个问题。

对于 ClassNotFoundException，答案始终是您的类路径中缺少一个类。在这种情况下，您缺少 com.mysql.jdbc.Driver，您已将其指定为 JDBC 驱动程序类。

假设您正在使用 maven，您将需要为 MySQL 驱动程序添加一个依赖项。如果您不使用 Maven，则需要下载 MySQL 驱动程序 jar 并将其放在您的 Web 应用程序的 WEB-INF/lib 目录中。