为什么Spring的FactoryBean getObject返回null？

感谢Sotirios Delimanolis评论，我得出了以下解决方案：

@Beanpublic ConversionServiceFactoryBean conversionService(Set<Converter<?, ?>> converters) {    final ConversionServiceFactoryBean factory = new ConversionServiceFactoryBean();    factory.setConverters(converters);    return factory;}

这实际上是以下配置的简写：

@Beanpublic ConversionService conversionService(Set<Converter<?, ?>> converters) {    final ConversionServiceFactoryBean factory = new ConversionServiceFactoryBean();    factory.setConverters(converters);    factory.afterPropertiesSet(); // necessary    return factory.getObject();}

工厂一直处于未完成状态，直到调用

afterPropertiesSet

ConversionServiceFactoryBean

ConversionService

InitializingBean

FactoryBean

afterPropertiesSet

getObject