SpringMVC:Write operations are not allowed in read-only mode (FlushMode.MANUAL)异常

org.springframework.dao.InvalidDataAccessApiUsageException: Write operations are not allowed in read-only mode (FlushMode.MANUAL): Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition.
at org.springframework.orm.hibernate4.HibernateTemplate.checkWriteOperationAllowed(HibernateTemplate.java:1128)
at org.springframework.orm.hibernate4.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:621)
at org.springframework.orm.hibernate4.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:618)
at org.springframework.orm.hibernate4.HibernateTemplate.doExecute(HibernateTemplate.java:341)
at org.springframework.orm.hibernate4.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:309)
at org.springframework.orm.hibernate4.HibernateTemplate.save(HibernateTemplate.java:618)
at com.dw.dao.impl.UserDaoImpl.save(UserDaoImpl.java:16)
at com.dw.service.impl.UserServiceImpl.add(UserServiceImpl.java:30)
at com.dw.controller.UserController.add(UserController.java:20)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:452)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1087)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:744)

今天遇到这个非常恶心的异常，用遍网上所有的方法都没有解决。藏的很隐蔽！我没有使用OpenSessionInViewFilter，自然就不存在它带来的异常；通过juit单独测试controller都没有错，于是开始怀疑是配置文件出了错……

在解决这个问题之前，先……

在很多项目中spring和springmvc整合时，都将spring的配置文件(管理IOC、AOP)和springmvc的配置文件（管理控制器）分开写；于是悲剧就诞生了，

出现的问题就是包扫描的范围：一般情况下springmvc的配置文件扫描controller：

<context:component-scan base-package="com.dw.controller"/>
<mvc:annotation-driven /> 修正之前是：
<context:component-scan base-package="com.dw"/>会报如上异常：

在spring的配置文件中报扫描范围：

<context:component-scan base-package="com.dw"/>

总结：最好不要将两个配置文件的扫描范围放在同一目录下。如果非要，可以指定扫描的注解，或不扫描的注解