汎用サービスと DAO 層を書きたい。
使用されるエンティティの UML は次のとおりです。
1.AbstractDAO
public interface AbstractDAO<T> {
public List<T> getAll();
}
2.AbstractDAOImpl
@Repository
public abstract class AbstractDAOImpl<T> implements AbstractDAO<T> {
private final Class<T> clazz = (Class<T>) ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
@Autowired
private SessionFactory sessionFactory;
@Override
public List<T> getAll() {
String query = "from " + clazz.getSimpleName().toString();
return sessionFactory.getCurrentSession().createQuery(query)
.list();
}
}
3.PaymentTypeDAO
public interface PaymentTypeDAO extends AbstractDAO<PaymentType> {
}
4.PaymentTypeDAOImpl
@Repository
public class PaymentTypeDAOImpl extends AbstractDAOImpl<PaymentType> implements PaymentTypeDAO {
@Autowired
private SessionFactory sessionFactory;
}
5. 抽象サービス
@Transactional
public interface AbstractService<T> {
@Transactional
public List<T> getAll();
}
6.AbstractServiceImpl
@Service
@Transactional
public class AbstractServiceImpl<T> implements AbstractService<T> {
@Autowired
private AbstractDAO<T> dao;
@Transactional
public List<T> getAll() {
return dao.getAll();
}
protected AbstractDAO<T> getDao() {
return dao;
}
protected void setDao(AbstractDAO<T> dao) {
this.dao = dao;
}
}
7.PaymentTypeService
@Transactional
public interface PaymentTypeService extends AbstractService<PaymentType> {
}
8.PaymentTypeServiceImpl
@Service
@Transactional
public class PaymentTypeServiceImpl extends AbstractServiceImpl<PaymentType> implements PaymentTypeService {
@Autowired
private PaymentTypeDAO paymentTypeDAO;
public PaymentTypeServiceImpl() {
super.setDao(paymentTypeDAO);
}
// @Override
// public List<PaymentType> getAll() {
// return paymentTypeDAO.getAll();
// }
//
}
コントローラーで自動配線PaymentTypeService
してから、メソッドを呼び出しますgetAll()
。しかし、それでも がスローNullPointerException
されます。ここにスタックトレース全体があります。
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:927)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
root cause
java.lang.NullPointerException
com.app.cloud.service.AbstractServiceImpl.getAll(AbstractServiceImpl.java:29)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
com.sun.proxy.$Proxy207.getAll(Unknown Source)
com.app.cloud.controller.orders.OrderController.edit(OrderController.java:150)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:746)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:687)
org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:915)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
getAll
でメソッド(コメント行)をオーバーライドするPaymentTypeServiceImpl
と、機能します。アドバイスいただけますか?