我正在开发一个Web应用程序,AngularJs作为前端,Spring+Hibernate作为服务层。服务层有一组由AngularJs使用的REST API。应用程序的前端没有什么大问题。但在服务层,我面临着一些并发问题。对于某些场景,我必须从同一个http会话对相同的REST API进行并行异步调用。当我这样做时,有几次我得到了上面的错误。2实际上,错误每次都在改变。3有时我也会在Query.List()操作上得到NULLPointerException。4有时我会得到TransactionResourceAlreadyClosed异常。5下面附上了各种配置和代码片段。
Web.xml
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>WEB-INF/config/fs-cxf-serverContext.xml,WEB-INF/config/fs-spring-jpa-config.xml,WEB-INF/config/security-beans.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<filter>
<filter-name>CorsFilter</filter-name>
<filter-class>org.apache.catalina.filters.CorsFilter</filter-class>
<init-param>
<param-name>cors.allowed.origins</param-name>
<param-value>*</param-value>
</init-param>
<init-param>
<param-name>cors.allowed.headers</param-name>
<param-value>Content-Type,X-Requested-With,accept,Origin,Access-Control-Request-Method,Access-Control-Request-Headers,Access-Control-Allow-Origin</param-value>
</init-param>
<init-param>
<param-name>cors.exposed.headers</param-name>
<param-value>Access-Control-Allow-Origin</param-value>
</init-param>
<init-param>
<param-name>cors.allowed.methods</param-name>
<param-value>GET, POST, PUT, DELETE, OPTIONS, HEAD</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CorsFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<description>Servlet to Initialize and shutdown the Scheduler</description>
<servlet-name>QuartzInitializer</servlet-name>
<servlet-class>org.quartz.ee.servlet.QuartzInitializerServlet</servlet-class>
<init-param>
<param-name>config-file</param-name>
<param-value>quartz.properties</param-value>
</init-param>
<init-param>
<param-name>shutdown-on-unload</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>start-scheduler-on-load</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet>
<servlet-name>CXFServlet</servlet-name>
<servlet-class>org.apache.cxf.transport.servlet.CXFServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>CXFServlet</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
<resource-ref>
<res-ref-name>jdbc/foodsafetyDS</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
<res-sharing-scope>Shareable</res-sharing-scope>
</resource-ref>
JPA配置
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.2.xsd">
<!-- Hibernate session factory -->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="entityInterceptor">
<bean class="com.cts.foodSafety.interceptor.AuditLogInterceptor"/>
</property>
</bean>
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<bean id="persistenceAnnotation"
class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />
<tx:annotation-driven transaction-manager="transactionManager" />
<task:annotation-driven/>
Hibernate.cfg.xml
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.datasource">java:comp/env/jdbc/foodsafetyDS</property>
<property name="hbm2ddl.auto">update</property>
<property name="show_sql">false</property>
<!-- Mapping with model class containing annotations -->
我已经使用CXF创建了一个简单的REST控制器。REST端点如下
@Path("/units")
@Produces(MediaType.APPLICATION_JSON)
public interface UnitService extends Serializable {
@GET
@Path("/getGraphData/{type}")
@Produces(MediaType.APPLICATION_JSON)
public UnitServiceBean getGraphData(@PathParam("type") String type)
throws FoodSafetyException;
}
控制器的实现如下
xxxServiceImpl.java
@Service("unit")
@Transactional
public class xxxServiceImpl implements xxxService {
private static final long serialVersionUID = 1L;
@Autowired
xxxDelegate xxxDelegate;
@Override
public UnitServiceBean getGraphData(String type) throws FoodSafetyException {
UnitServiceBean bean = new UnitServiceBean();
List<String[]> data = unitDelegate.getGraphData(type);
....
....
return bean;
}
Delegate调用DAO(目前还没有引入Business对象),DAO的实现如下
@Component
public class UnitDAOImpl extends FoodSafetyDAO implements UnitDAO {
@Override
public List<String[]> getGraphData(String type) {
List<String[]> data = new ArrayList<String[]>();
Map<String, List<UnitReadingEntity>> readings = new HashMap<String, List<UnitReadingEntity>>();
SimpleDateFormat df = CommonConstants.TIME_FORMATTER;
// Get all the Units
Query query = getSession().getNamedQuery(
QueryConstants.FIND_UNITS_BY_TYPE);
query.setParameter(QueryConstants.TYPE, type);
List<UnitEntity> units = (List<UnitEntity>) query.list();
if (units != null && units.size() != 0) {
.....
.....
for (UnitEntity unit : units) {
Calendar cal1 = Calendar.getInstance();
cal1.add(Calendar.DAY_OF_YEAR, -1);
query = getSession().getNamedQuery(
QueryConstants.FIND_READING_BY_UNIT_TIME).setLong(
QueryConstants.UNIT_ID, unit.getUnitId());
List<UnitReadingEntity> rr = query.list();
...
...
}
}
return data;
}
现在,当我使用POSTMAN等调用REST服务“getGraphData”一次时,它工作正常,没有任何问题。但是当我使用模拟并发调用此REST服务时,我得到以下错误
Caused by: org.hibernate.AssertionFailure: possible non-threadsafe access to the session
at org.hibernate.engine.internal.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:130)
at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:1108)
at org.hibernate.loader.Loader.processResultSet(Loader.java:964)
at org.hibernate.loader.Loader.doQuery(Loader.java:911)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:342)
at org.hibernate.loader.Loader.doList(Loader.java:2526)
at org.hibernate.loader.Loader.doList(Loader.java:2512)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2342)
at org.hibernate.loader.Loader.list(Loader.java:2337)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:495)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:356)
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:195)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1269)
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
at com.cts.foodSafety.model.dao.impl.UnitDAOImpl.getGraphData(UnitDAOImpl.java:255)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:51)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:42)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy51.getGraphData(Unknown Source)
at com.cts.foodSafety.delegate.UnitDelegate.getGraphData(UnitDelegate.java:39)
at com.cts.foodSafety.delegate.UnitDelegate$$FastClassByCGLIB$$aac35d0d.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:51)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:42)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
at com.cts.foodSafety.delegate.UnitDelegate$$EnhancerByCGLIB$$75af66.getGraphData(<generated>)
at com.cts.foodSafety.service.impl.UnitServiceImpl.getGraphData(UnitServiceImpl.java:108)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:51)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:42)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:55)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy72.getGraphData(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.cxf.service.invoker.AbstractInvoker.performInvocation(AbstractInvoker.java:180)
at org.apache.cxf.service.invoker.AbstractInvoker.invoke(AbstractInvoker.java:96)
我用来进行并发请求的客户端如下
public class RestClient implements Runnable{
private String i;
public RestClient(String x) {
i=x;
}
public static void main(String[] args) {
for(int i =1;i<=2;i++) {
Thread t = new Thread(new RestClient(String.valueOf(i)));
t.start();
}
}
@Override
public void run() {
System.out.println("started " + i);
try {
URL url = new URL(" http://localhost:8080/fs/services/units/getGraphData/Freezer");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept", "application/json");
if (conn.getResponseCode() != 204) {
throw new RuntimeException("Failed : HTTP error code : "
+ conn.getResponseCode());
}
有什么建议吗?我已经看了很多关于Spring+Hibernate中的会话和事务管理的材料。但是我不能解决这个问题。
1条答案
按热度按时间iq0todco1#
我认为,如果您像这样使用Hibernate,那么您应该通过调用
getSession(false)
来获取会话,以确保将会话绑定到事务。这在Spring文档中的实现基于Spring的DAO而不使用回调一章中进行了解释:* 这类代码通常会传递false作为getSession(..)方法allowCreate参数的值,以强制在事务内运行(这避免了关闭返回的Session的需要,因为它的生命周期由事务管理)。*