Spring-Boot需要构造函数中的通用类型

Question

我在代码中遇到了一个问题，我正在寻找解决方法。这是一节课：

import org.axonframework.eventhandling.EventBus;
import org.axonframework.eventsourcing.EventSourcedAggregateRoot;
import org.axonframework.eventsourcing.EventSourcingRepository;
import org.axonframework.eventstore.EventStore;
import org.axonframework.repository.LockManager;
import org.axonframework.repository.PessimisticLockManager;
import org.axonframework.repository.Repository;
import org.springframework.stereotype.Component;

@Component
public class BaseCommandHandler<E extends EventSourcedAggregateRoot> {

  protected Repository<E> repository;
  protected LockManager lockManager;

  /**
   * @param eventBus eventBus.
   * @param eventStore eventStore.
   */
  public BaseCommandHandler(EventBus eventBus, EventStore eventStore) {
    this.lockManager = new PessimisticLockManager();
    EventSourcingRepository<E> newRepository =
        new EventSourcingRepository<>(E.class, eventStore, lockManager);
    newRepository.setEventBus(eventBus);
  }
}

我面临的第一个问题是我不能使用E.class。然后，我将构造函数更改为以下内容：

  public BaseCommandHandler(EventBus eventBus, EventStore eventStore, Class<E> type) {
    this.lockManager = new PessimisticLockManager();
    EventSourcingRepository<E> newRepository =
        new EventSourcingRepository<>(type, eventStore, lockManager);
    newRepository.setEventBus(eventBus);
  }
}

但当我运行应用程序时，由于com中构造函数的参数2，它无法启动。领域处理程序。BaseCommandHandler需要“java”类型的bean。“lang.Class”无法找到

我如何解决这个问题？

Answer 1

您可以使用GenericTypeResolver类：

Class<E> type = (Class<E>) GenericTypeResolver.resolveTypeArgument(getClass(), BaseCommandHandler.class);
EventSourcingRepository<E> newRepository = new EventSourcingRepository<>(type, eventStore, lockManager);