EntityManager不会被Guice注入

import javax.inject.Provider;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

public class EntityManagerProvider implements Provider<EntityManager> {
    private static final EntityManagerFactory emf = Persistence.createEntityManagerFactory("persistence-unit-name");

    @Override
    public EntityManager get() {
        return emf.createEntityManager();
    }
}

import com.google.inject.AbstractModule;

public class MyModule extends AbstractModule {
    @Override
    protected void configure() {
        bind(EntityManager.class).toProvider(EntityManagerProvider.class);
    }
}

import com.google.inject.Guice;
import com.google.inject.Injector;

public class MyApp {
    public static void main(String[] args) {
        Injector injector = Guice.createInjector(new MyModule());
        // 使用注入的EntityManager进行持久化操作
        EntityManager entityManager = injector.getInstance(EntityManager.class);
        // ...
    }
}