Mar*_*hel 14 java generics decorator cdi
我有以下结构:
@Decorator
public abstract class MyDecorator<T extends BaseEntity, Q extends QueryParams> implements EntityService<T, Q> {
@Any
@Inject
@Delegate
EntityService<T, Q> delegate;
@Override
public T save(T entity) { ... }
}
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这是EntityService接口声明:
public interface EntityService<T extends BaseEntity, Q extends QueryParams> {
T save(T entity);
void deleteById(Integer id);
void deleteAllById(List<Integer> ids);
void delete(T entity);
void deleteAll(List<T> entities);
T findById(Integer id);
QueryResultWrapper<T> query(Q parameters);
Long count(Q parameters);
}
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不幸的是,装饰器保存方法永远不会被调用,虽然没有显示错误...我得到它的唯一方法是这样:
@Decorator
public abstract class MyDecorator<T extends BaseEntity> implements EntityService<T> { ... }
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没有Q extends QueryParams通用的参数.
在MyDecorator里面宣布beans.xml.
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/beans_1_1.xsd"
bean-discovery-mode="all" version="1.1">
<decorators>
<class>fortuna.backend.comum.decorators.MyDecorator</class>
</decorators>
</beans>
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有线索吗?
设法解决了问题。我的问题是我QueryParams直接在大多数端点/服务实现中使用,例如:
public class PersonService extends EntityService<Person, QueryParams> { ... }
事实上,其实QueryParams不是extends QueryParams,它是类本身!这就是为什么根本PersonService没有触发!MyDecorator
因此,我创建了一个名为IQueryParams并使用它的接口,如下所示:
public abstract class MyDecorator<T extends BaseEntity, Q extends IQueryParams> implements EntityService<T, Q> {
现在PersonServicesave 方法确实触发了MyDecorator.