如何在 Spring 单例控制器中注入原型 bean

Question

我有一个用于原型 bean 的 FactoryBean，如下所示：

@Component
public class ApplicationConfigurationMergedPropertiesFactoryBean implements SmartFactoryBean<Properties>{

    @Autowired
    protected ApplicationConfigurationInitializer initializer;

    @Override
    public Properties getObject() throws Exception {
        return XXXXXXXXXX;
    }

    @Override
    public Class<?> getObjectType() {
        return Properties.class;
    }

    @Override
    public boolean isSingleton() {
        return false;
    }

    @Override
    public boolean isPrototype() {
        return true;
    }

我想在控制器中自动装配它，并且每当我尝试访问属性时（通过p.get()，从ApplicationConfigurationMergedPropertiesFactoryBean.getObject() 获得一个新原型实例：

@Controller
@RequestMapping("/home")
public class HomeController {

  @Autowired
  @Qualifier("applicationConfig")
  private Properties p;

  @RequestMapping(method = { RequestMethod.GET, RequestMethod.POST })
  public String home() {
        System.out.println(p.get("something"));
  }

但是这从不调用 getObject()。如果我注入 ApplicationContext 并直接访问 bean，它就可以工作，提供一个全新的 Properties bean：

@Controller
@RequestMapping("/home")
public class HomeController {

    @Autowired
    @Qualifier("applicationConfig")
    private Properties p;

    @Autowired
    private ApplicationContext ac;

    @RequestMapping(method = { RequestMethod.GET, RequestMethod.POST })
    public String home() {
        System.out.println(p.get("something"));  //WRONG!!!!
        System.out.println(ac.getBean("applicationConfig", Properties.class).getProperty("something")); //OK!!!!

如何使用@Autowired 注入直接实现这一点？

Answer 1

您是否考虑过将控制器类也设为原型范围？

@Controller
@Scope("prototype")
@RequestMapping("/home")
public class HomeController {

Answer 2

直接注入工厂：

@Controller
@RequestMapping("/home")
public class HomeController {

    @Autowired
    @Qualifier("applicationConfig")
    private SmartFactoryBean p;

    @Autowired
    private ApplicationContext ac;

    @RequestMapping(method = { RequestMethod.GET, RequestMethod.POST })
    public String home() {
        System.out.println(p.getObject()); 
   ....
   }