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我正在尝试为我的 SAAS 产品实现 Multi-Tenancy 架构方法(每个租户的单独架构),我尝试在我的 MultiTenantConnectionProviderImpl 中 Autowiring 数据源 bean,但它给了我空指针异常。下面是我的代码。
Spring session 文件:-
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close" p:driverClassName="${app.jdbc.driverClassName}"
p:url="${app.jdbc.databaseurl}" p:username="${app.jdbc.username}"
p:password="${app.jdbc.password}"/>
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation">
<value>classpath:hibernate.applicationDB.cfg.xml</value>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">${app.jdbc.dialect}</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.connection.autoReconnect">true</prop>
<prop key="connection.autoReconnectForPools">true</prop>
<prop key="connection.is-connection-validation-required">true</prop>
<prop key="hibernate.c3p0.minPoolSize">5</prop>
<prop key="hibernate.c3p0.maxPoolSize">100</prop>
<prop key="hibernate.c3p0.timeout">1800</prop>
<prop key="hibernate.c3p0.max_statement">55</prop>
<prop key="hibernate.c3p0.idle_test_period">2000</prop>
<prop key="hibernate.c3p0.numHelperThreads">20</prop>
<prop key="hibernate.multiTenancy">SCHEMA</prop>
<prop key="hibernate.tenant_identifier_resolver">com.elecnor.ecosystem.hibernate.CurrentTenantIdentifierResolverImpl</prop>
<prop key="hibernate.multi_tenant_connection_provider">com.elecnor.ecosystem.hibernate.MultiTenantConnectionProviderImpl</prop>
</props>
</property>
</bean>
<bean id="currentTenantIdentifierResolverImpl"
class="com.elecnor.ecosystem.hibernate.CurrentTenantIdentifierResolverImpl" scope="request">
<aop:scoped-proxy/>
</bean>
<bean id="multiTenantConnectionProviderImpl" class="com.elecnor.ecosystem.hibernate.MultiTenantConnectionProviderImpl">
<property name="dataSource" ref="dataSource"/>
</bean>
MultiTenantConnectionProviderImpl 代码:-
@Component
public class MultiTenantConnectionProviderImpl implements MultiTenantConnectionProvider{
@Autowired
@Qualifier("dataSource")
DataSource dataSource;
@Override
public boolean isUnwrappableAs(Class arg0) {
// TODO Auto-generated method stub
return false;
}
@Override
public <T> T unwrap(Class<T> arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public Connection getAnyConnection() throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== Get any connetion === ");
// Start
//BasicDataSource dataSource = new BasicDataSource();
// End
try {
if(dataSource==null)
System.out.println("dataSource null.. ");
else
System.out.println("dataSource not null.. ");
System.out.println(dataSource.getConnection().createStatement().executeQuery("select 1 from dual").toString());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return dataSource.getConnection();
}
@Override
public Connection getConnection(String tenantId) throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== Get connetion === ");
return dataSource.getConnection();
}
@Override
public void releaseAnyConnection(Connection arg0) throws SQLException {
// TODO Auto-generated method stub
}
@Override
public void releaseConnection(String arg0, Connection arg1)
throws SQLException {
// TODO Auto-generated method stub
}
@Override
public boolean supportsAggressiveRelease() {
// TODO Auto-generated method stub
return false;
}
/**
* @return the dataSource
*/
public DataSource getDataSource() {
return dataSource;
}
/**
* @param dataSource the dataSource to set
*/
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
下面是我遇到的异常,有人可以帮我解决这个问题吗?
dataSource null..
java.lang.NullPointerException
at com.elecnor.ecosystem.hibernate.MultiTenantConnectionProviderImpl.getAnyConnection(MultiTenantConnectionProviderImpl.java:57)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl$MultiTenantConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcServicesImpl.java:265)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:117)
at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:76)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:160)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:132)
at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1825)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1783)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1868)
at org.springframework.orm.hibernate4.LocalSessionFactoryBuilder.buildSessionFactory(LocalSessionFactoryBuilder.java:339)
at org.springframework.orm.hibernate4.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:427)
at org.springframework.orm.hibernate4.LocalSessionFactoryBean.afterPropertiesSet(LocalSessionFactoryBean.java:412)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1612)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1549)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1014)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:957)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:855)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:480)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1014)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:957)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:855)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:480)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:643)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:606)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:657)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:525)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:466)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5229)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5516)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1575)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1565)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
May 05, 2015 12:07:17 PM org.apache.catalina.core.ApplicationContext log
SEVERE: StandardWrapper.Throwable
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'addressDetailsController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.elecnor.ecosystem.dao.AddressDetailsDAO com.elecnor.ecosystem.controller.AddressDetailsController.addressDetailsDAO; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'addressDetailsDAOImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: org.hibernate.SessionFactory com.elecnor.ecosystem.daoimpl.AddressDetailsDAOImpl.sessionFactory; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]: Invocation of init method failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:292)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:643)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:606)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:657)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:525)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:466)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5229)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5516)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1575)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1565)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.elecnor.ecosystem.dao.AddressDetailsDAO com.elecnor.ecosystem.controller.AddressDetailsController.addressDetailsDAO; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'addressDetailsDAOImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: org.hibernate.SessionFactory com.elecnor.ecosystem.daoimpl.AddressDetailsDAOImpl.sessionFactory; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]: Invocation of init method failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:508)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289)
... 29 more
最佳答案
我深入研究了这个问题,发现当前版本的 spring 没有管理 Multi-Tenancy 实现类,这就是为什么没有将 dataSource 注入(inject)到实现类中的原因。请访问以下链接:- https://jira.spring.io/browse/SPR-10823#comment-94855
我使用 Hibernate 服务注册表将数据源注入(inject)到此类中。请参阅下面的代码:- 公共(public)类 MultiTenantConnectionProviderImpl 实现 MultiTenantConnectionProvider、ServiceRegistryAwareService{
DataSource dataSource;
@Override
public void injectServices(ServiceRegistryImplementor serviceRegistry) {
Map lSettings = serviceRegistry.getService(ConfigurationService.class).getSettings();
System.out.println(" ********************** " + Environment.DATASOURCE );
System.out.println(" ********************** " + lSettings.get( Environment.DATASOURCE ) );
dataSource = (DataSource) lSettings.get( Environment.DATASOURCE );
}
@Override
public boolean isUnwrappableAs(Class unwrapType) {
// TODO Auto-generated method stub
return ConnectionProvider.class.equals( unwrapType )
|| MultiTenantConnectionProvider.class.equals( unwrapType )
|| MultiTenantConnectionProviderImpl.class.isAssignableFrom( unwrapType );
}
@Override
public <T> T unwrap(Class<T> unwrapType) {
// TODO Auto-generated method stub
if ( isUnwrappableAs( unwrapType ) ) {
return (T) this;
}
else {
throw new UnknownUnwrapTypeException( unwrapType );
}
}
@Override
public Connection getAnyConnection() throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== Get any connetion === ");
try {
dataSource.getConnection();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return dataSource.getConnection();
}
@Override
public Connection getConnection(String tenantId) throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== Get connetion === ");
System.out.println("=== Tenant ID = "+tenantId);
return getAnyConnection();
}
@Override
public void releaseAnyConnection(Connection connection) throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== releaseAnyConnection=== ");
try {
connection.close();
}catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public void releaseConnection(String tenantId, Connection connection)
throws SQLException {
// TODO Auto-generated method stub
System.out.println("=== releaseConnection=== ");
try {
this.releaseAnyConnection(connection);
}catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public boolean supportsAggressiveRelease() {
// TODO Auto-generated method stub
System.out.println("=== supportsAggressiveRelease=== ");
return false;
}
关于java - Spring - Hibernate Multi-Tenancy 问题,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30046175/
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