org.springframework.beans.factory.config

Class PropertiesFactoryBean

    • Constructor Detail

      • PropertiesFactoryBean

        public PropertiesFactoryBean()
    • Method Detail

      • setSingleton

        public final void setSingleton(boolean singleton)
        Set whether a shared 'singleton' Properties instance should be created, or rather a new Properties instance on each request.

        Default is "true" (a shared singleton).

      • isSingleton

        public final boolean isSingleton()
        Description copied from interface: FactoryBean
        Is the object managed by this factory a singleton? That is, will FactoryBean.getObject() always return the same object (a reference that can be cached)?

        NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from getObject() might get cached by the owning BeanFactory. Hence, do not return true unless the FactoryBean always exposes the same reference.

        The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.

        NOTE: This method returning false does not necessarily indicate that returned objects are independent instances. An implementation of the extended SmartFactoryBean interface may explicitly indicate independent instances through its SmartFactoryBean.isPrototype() method. Plain FactoryBean implementations which do not implement this extended interface are simply assumed to always return independent instances if the isSingleton() implementation returns false.

        The default implementation returns true, since a FactoryBean typically manages a singleton instance.

        Specified by:
        isSingleton in interface FactoryBean<java.util.Properties>
        Returns:
        whether the exposed object is a singleton
        See Also:
        FactoryBean.getObject(), SmartFactoryBean.isPrototype()
      • afterPropertiesSet

        public final void afterPropertiesSet()
                                      throws java.io.IOException
        Description copied from interface: InitializingBean
        Invoked by the containing BeanFactory after it has set all bean properties and satisfied BeanFactoryAware, ApplicationContextAware etc.

        This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.

        Specified by:
        afterPropertiesSet in interface InitializingBean
        Throws:
        java.io.IOException
      • getObject

        @Nullable
        public final java.util.Properties getObject()
                                                       throws java.io.IOException
        Description copied from interface: FactoryBean
        Return an instance (possibly shared or independent) of the object managed by this factory.

        As with a BeanFactory, this allows support for both the Singleton and Prototype design pattern.

        If this FactoryBean is not fully initialized yet at the time of the call (for example because it is involved in a circular reference), throw a corresponding FactoryBeanNotInitializedException.

        As of Spring 2.0, FactoryBeans are allowed to return null objects. The factory will consider this as normal value to be used; it will not throw a FactoryBeanNotInitializedException in this case anymore. FactoryBean implementations are encouraged to throw FactoryBeanNotInitializedException themselves now, as appropriate.

        Specified by:
        getObject in interface FactoryBean<java.util.Properties>
        Returns:
        an instance of the bean (can be null)
        Throws:
        java.io.IOException
        See Also:
        FactoryBeanNotInitializedException
      • getObjectType

        public java.lang.Class<java.util.Properties> getObjectType()
        Description copied from interface: FactoryBean
        Return the type of object that this FactoryBean creates, or null if not known in advance.

        This allows one to check for specific types of beans without instantiating objects, for example on autowiring.

        In the case of implementations that are creating a singleton object, this method should try to avoid singleton creation as far as possible; it should rather estimate the type in advance. For prototypes, returning a meaningful type here is advisable too.

        This method can be called before this FactoryBean has been fully initialized. It must not rely on state created during initialization; of course, it can still use such state if available.

        NOTE: Autowiring will simply ignore FactoryBeans that return null here. Therefore it is highly recommended to implement this method properly, using the current state of the FactoryBean.

        Specified by:
        getObjectType in interface FactoryBean<java.util.Properties>
        Returns:
        the type of object that this FactoryBean creates, or null if not known at the time of the call
        See Also:
        ListableBeanFactory.getBeansOfType(java.lang.Class<T>)
      • createProperties

        protected java.util.Properties createProperties()
                                                 throws java.io.IOException
        Template method that subclasses may override to construct the object returned by this factory. The default implementation returns the plain merged Properties instance.

        Invoked on initialization of this FactoryBean in case of a shared singleton; else, on each getObject() call.

        Returns:
        the object returned by this factory
        Throws:
        java.io.IOException - if an exception occurred during properties loading
        See Also:
        PropertiesLoaderSupport.mergeProperties()