当实例化 BaseDaoImpl的时候报错：
java.lang.ExceptionInInitializerError
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at org.junit.runners.BlockJUnit4ClassRunner.createTest(BlockJUnit4ClassRunner.java:178) at org.junit.runners.BlockJUnit4ClassRunner$1.runReflectiveCall(BlockJUnit4ClassRunner.java:227) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:224) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:69) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:48) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222) at org.junit.runners.ParentRunner.run(ParentRunner.java:292) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197) Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'baseDao' defined in file [D:\Workspaces\zgyl\target\classes\com\gyl\base\dao\impl\BaseDaoImpl.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.gyl.base.dao.impl.BaseDaoImpl]: 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:1013) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:959) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:626) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83) at com.gyl.test.utils.SpringUtils.<clinit>(SpringUtils.java:11) ... 22 more Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.gyl.base.dao.impl.BaseDaoImpl]: 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:87) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1006) ... 35 more Caused by: java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType at com.gyl.base.dao.impl.BaseDaoImpl.<init>(BaseDaoImpl.java:48) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)... 37 more
原因 ：
/** * @Title: BaseDaoImpl * @Description: 把泛型的参数提取出来的过程放入到构造函数中写, * 因为当子类创建对象的时候, 直接调用父类的构造函数 * BaseDaoImpl 不能实例化 * 如果不带 T, this.getClass().getGenericSuperClass()返回的时Class类型, * 而不是 ParameterizedType, Spring(2.x和3.x) 容器不支持带泛型的创建对象 * @param: * @throws */
