TransactionProxyFactoryBean 代理事务 $Proxy9 cannot be cast to异常解决方法

异常如下：

[com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor]-[ERROR] $Proxy9 cannot be cast to com.student.service.StudentService

java.lang.ClassCastException: $Proxy5 cannot
be cast to com.student.service.StudentService

解决方法：

导致出问题的代码片段：

//userService定义为接口类型！！！ 不能是实现类类型

private static
UserServiceBean userService;

@BeforeClass

public static void setUpBeforeClass() throws Exception {

try {

ApplicationContext cat = new ClassPathXmlApplicationContext("beans.xml");

userService = (UserServiceBean) cat.getBean("userServiceBean");

} catch (RuntimeException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

正确代码：

private static UserService userService;

@BeforeClass

public static void setUpBeforeClass() throws Exception {

try {

ApplicationContext cat = new ClassPathXmlApplicationContext("beans.xml");

userService = (UserService) cat.getBean("userServiceBean");

} catch (RuntimeException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

这主要代理需要用到接口

Ps: 所以通过这种代理的话，必须声明一个接口（例如Service），并在接口中声明实现类（例如： UserService）所需要的方法，这样 userService = (UserService)
cat.getBean("userServiceBean")

其中把 private static UserService userService 写成了 private static UserServiceBean userService