BaseServiceImp.java
package com.cqb.service; import java.lang.reflect.ParameterizedType; import java.util.List; import org.hibernate.Session; import org.hibernate.SessionFactory; import com.cqb.tools.GenericsUtils; @SuppressWarnings("unchecked") public class BaseServiceImp<T> implements BaseService<T> { private Class<T> clazz; private SessionFactory sessionFactory; public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } public BaseServiceImp() { // TODO Auto-generated constructor stub //ParameterizedType type = (ParameterizedType) this.getClass().getGenericSuperclass(); //clazz = (Class)type.getActualTypeArguments()[0]; ParameterizedType type = (ParameterizedType) this.getClass().getGenericSuperclass(); clazz = (Class)type.getActualTypeArguments()[0]; } @Override public void save(T t) { // TODO Auto-generated method stub getSession().save(t); } @Override public void update(T t) { // TODO Auto-generated method stub getSession().update(t); } @Override public void delete(int i) { // TODO Auto-generated method stub String hql = "delete "+ clazz.getSimpleName() +" as c where c.id=:id"; getSession().createQuery(hql) .setInteger("id", i) .executeUpdate(); } @Override public T get(int id) { // TODO Auto-generated method stub return (T) getSession().get(clazz, id); } @Override public List<T> qurey() { // TODO Auto-generated method stub System.out.println(clazz.getSimpleName()+"-----------------------"); String hql = "from " + clazz.getSimpleName(); return getSession().createQuery(hql).list(); //return null; } protected Session getSession() { return sessionFactory.getCurrentSession(); } }
spring文件中service配置
<!-- 配置Service --> <bean id="baseService" class="com.cqb.service.BaseServiceImp"> <property name="sessionFactory" ref="sessionFactory"/> </bean> 错误信息 严重: Context initialization failed org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'baseService' defined in class path resource [beans.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.cqb.service.BaseServiceImp]: Constructor threw exception; nested exception is java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1105) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1050) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:446) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:328) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:107) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5118) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5634) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1571) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1561) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.cqb.service.BaseServiceImp]: Constructor threw exception; nested exception is java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1098) ... 22 more Caused by: java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at com.cqb.service.BaseServiceImp.<init>(BaseServiceImp.java:23) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147) ... 24 more 四月 13, 2017 10:40:47 下午 org.apache.catalina.core.StandardContext listenerStart 严重: 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 'baseService' defined in class path resource [beans.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.cqb.service.BaseServiceImp]: Constructor threw exception; nested exception is java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1105) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1050) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:446) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:328) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:107) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5118) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5634) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1571) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1561) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.cqb.service.BaseServiceImp]: Constructor threw exception; nested exception is java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1098) ... 22 more Caused by: java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at com.cqb.service.BaseServiceImp.<init>(BaseServiceImp.java:23) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147) ... 24 more Constructor threw exception; nested exception is java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType在创建BaseService时报错 类型转换失败泛型是无法实例化的 所以要在spring中配置延迟加载
<!-- 配置Service --> <bean id="baseService" class="com.cqb.service.BaseServiceImp" lazy-init="true"> <property name="sessionFactory" ref="sessionFactory"/> </bean>问题解决
