Spring Java Config:如何创建带有运行时参数的prototype作用域@Bean？

@Autowired
private ApplicationContext appCtx;
public void onRequest(Request request) {
    //request is already validated
    String name = request.getParameter("name");
    Thing thing = appCtx.getBean(Thing.class, name);
    //System.out.println(thing.getName()); //prints name
}

public class Thing {
    private final String name;
    @Autowired
    private SomeComponent someComponent;
    @Autowired
    private AnotherComponent anotherComponent;
    public Thing(String name) {
        this.name = name;
    public String getName() {
        return this.name;
}

<bean id="thing", class="com.whatever.Thing" scope="prototype">
    <!-- other post-instantiation properties omitted -->
</bean>

@Bean
@Scope("prototype")
public Thing thing(String name) {
    return new Thing(name);
}

public interface ThingFactory {
    public Thing createThing(String name);
}

@Bean
@Scope("prototype")
public Thing thing(String name) {
    return new Thing(name);
}

@Autowired
private ObjectProvider<Thing> things;
[...]
Thing newThing = things.getObject(name);
[...]

@Configuration
public class ServiceConfig {
    // only here to demo execution order
    private int count = 1;
    @Bean
    @Scope(value = "prototype")
    public TransferService myFirstService(String param) {
       System.out.println("value of count:" + count++);
       return new TransferServiceImpl(aSingletonBean(), param);
    @Bean
    public AccountRepository aSingletonBean() {
        System.out.println("value of count:" + count++);
        return new InMemoryAccountRepository();
}

@Test
public void prototypeTest() {
    // create the spring container using the ServiceConfig @Configuration class
    ApplicationContext ctx = new AnnotationConfigApplicationContext(ServiceConfig.class);
    Object singleton = ctx.getBean("aSingletonBean");
    System.out.println(singleton.toString());
    singleton = ctx.getBean("aSingletonBean");
    System.out.println(singleton.toString());
    TransferService transferService = ctx.getBean("myFirstService", "simulated Dynamic Parameter One");
    System.out.println(transferService.toString());
    transferService = ctx.getBean("myFirstService", "simulated Dynamic Parameter Two");
    System.out.println(transferService.toString());
}

value of count:1
com.spring3demo.account.repository.InMemoryAccountRepository@4da8692d
com.spring3demo.account.repository.InMemoryAccountRepository@4da8692d
value of count:2
Using name value of: simulated Dynamic Parameter One
com.spring3demo.account.service.TransferServiceImpl@634d6f2c
value of count:3
Using name value of: simulated Dynamic Parameter Two
com.spring3demo.account.service.TransferServiceImpl@70bde4a2

public class TransferServiceImpl implements TransferService {
    private final String name;
    private final AccountRepository accountRepository;
    public TransferServiceImpl(AccountRepository accountRepository, String name) {
        this.name = name;
        // system out here is only because this is a dumb test usage
        System.out.println("Using name value of: " + this.name);
        this.accountRepository = accountRepository;
}

/**
 * Return an instance, which may be shared or independent, of the specified bean.
 * <p>Allows for specifying explicit constructor arguments / factory method arguments,
 * overriding the specified default arguments (if any) in the bean definition.
 * @param name the name of the bean to retrieve
 * @param args arguments to use if creating a prototype using explicit arguments to a
 * static factory method. It is invalid to use a non-null args value in any other case.
 * @return an instance of the bean
 * @throws NoSuchBeanDefinitionException if there is no such bean definition
 * @throws BeanDefinitionStoreException if arguments have been given but
 * the affected bean isn't a prototype
 * @throws BeansException if the bean could not be created
 * @since 2.5
Object getBean(String name, Object... args) throws BeansException;

@Configuration    
public class ServiceConfig {
    @Bean
    public Function<String, Thing> thingFactory() {
        return name -> thing(name); // or this::thing
    @Bean
    @Scope(value = "prototype")
    public Thing thing(String name) {
       return new Thing(name);
}

@Autowired
private Function<String, Thing> thingFactory;
public void onRequest(Request request) {
    //request is already validated
    String name = request.getParameter("name");
    Thing thing = thingFactory.apply(name);
    // ...
}

@Configuration
public class MyConf {
    @Bean
    @Scope(BeanDefinition.SCOPE_PROTOTYPE)
    public MyPrototype createPrototype(String arg) {
        return new MyPrototype(arg);
public class MyPrototype {
    private String arg;
    public MyPrototype(String arg) {
        this.arg = arg;
    public void action() {
        System.out.println(arg);
@Component
public class UsingMyPrototype {
    private ObjectProvider<MyPrototype> myPrototypeProvider;
    @Autowired
    public UsingMyPrototype(ObjectProvider<MyPrototype> myPrototypeProvider) {
        this.myPrototypeProvider = myPrototypeProvider;
    public void usePrototype() {
        final MyPrototype myPrototype = myPrototypeProvider.getObject("hello");
        myPrototype.action();
}

@Component
class ThingFactory {
    private final SomeBean someBean;
    ThingFactory(SomeBean someBean) {
        this.someBean = someBean;
    Thing getInstance(String name) {
        return new Thing(name);
    class Thing {
        private final String name;
        Thing(String name) {
            this.name = name;
        void foo() {
            System.out.format("My name is %s and I can " +
                    "access bean from outer class %s", name, someBean);
}

@Configuration    
public class ServiceFactory {
    @Bean
    @Scope(value = ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    public Thing thing(String name) {
       return new Thing(name);
}

@Autowired
private ServiceFactory serviceFactory;
public void onRequest(Request request) {
    //request is already validated
    String name = request.getParameter("name");
    Thing thing = serviceFactory.thing(name); // create a new bean at each invocation
    // ...    
}

@Configuration
public class ThingConfiguration {
   @Bean
   @Scope(SCOPE_PROTOTYPE)
   public Thing simpleThing(String name) {
       return new Thing(name);
   @Bean
   @Scope(SCOPE_PROTOTYPE)
   public Thing specialThing(String name) {
       Thing thing = new Thing(name);
       // some special configuration
       return thing;
// Usage

Spring Java Config:如何创建带有运行时参数的prototype作用域@Bean？

8 个回答