Package org.springframework.beans.factory.config

Class YamlPropertiesFactoryBean

java.lang.Object
org.springframework.beans.factory.config.YamlProcessor
org.springframework.beans.factory.config.YamlPropertiesFactoryBean
All Implemented Interfaces:
FactoryBean<Properties>, InitializingBean
public class YamlPropertiesFactoryBean extends YamlProcessor implements FactoryBean<Properties>, InitializingBean
Factory for Properties that reads from a YAML source, exposing a flat structure of String property values.

YAML is a nice human-readable format for configuration, and it has some useful hierarchical properties. It's more or less a superset of JSON, so it has a lot of similar features.

Note: All exposed values are of type String for access through the common Properties.getProperty(java.lang.String) method (e.g. in configuration property resolution through PropertiesLoaderSupport.setProperties(Properties)). If this is not desirable, use YamlMapFactoryBean instead.

The Properties created by this factory have nested paths for hierarchical objects, so for instance this YAML 

 environments:
   dev:
     url: https://dev.bar.com
     name: Developer Setup
   prod:
     url: https://foo.bar.com
     name: My Cool App
is transformed into these properties: 
 environments.dev.url=https://dev.bar.com
 environments.dev.name=Developer Setup
 environments.prod.url=https://foo.bar.com
 environments.prod.name=My Cool App
Lists are split as property keys with [] dereferencers, for example this YAML: 
 servers:
 - dev.bar.com
 - foo.bar.com
becomes properties like this: 
 servers[0]=dev.bar.com
 servers[1]=foo.bar.com

Requires SnakeYAML 2.0 or higher, as of Spring Framework 6.1.

Since:
4.1
Author:
Dave Syer, Stephane Nicoll, Juergen Hoeller

  • Constructor Details

    • YamlPropertiesFactoryBean

      public YamlPropertiesFactoryBean()

  • Method Details

    • setSingleton

      public void setSingleton(boolean singleton)
      Set if a singleton should be created, or a new object on each request otherwise. Default is true (a singleton).

    • isSingleton

      public 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<Properties>
      Returns:
      whether the exposed object is a singleton
      See Also:

    • afterPropertiesSet

      public void afterPropertiesSet()
      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

    • getObject

      @Nullable public Properties getObject()
      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<Properties>
      Returns:
      an instance of the bean (can be null)
      See Also:

    • getObjectType

      public Class<?> 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<Properties>
      Returns:
      the type of object that this FactoryBean creates, or null if not known at the time of the call
      See Also:

    • createProperties

      protected Properties createProperties()
      Template method that subclasses may override to construct the object returned by this factory. The default implementation returns a properties with the content of all resources.

      Invoked lazily the first time getObject() is invoked in case of a shared singleton; else, on each getObject() call.

      Returns:
      the object returned by this factory
      See Also: