public final  void afterPropertiesSet() throws IOException 
{
		if (this.singleton) {
			this.singletonInstance = createInstance();
		}
}

 protected Object createInstance() throws IOException 
{
		return mergeProperties();
}

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.

 public final Object getObject() throws IOException 
{
		if (this.singleton) {
			return this.singletonInstance;
		}
		else {
			return createInstance();
		}
}

 public Class getObjectType() 
{
		return Properties.class;
}

 public final boolean isSingleton() 
{
		return this.singleton;
}

 public final  void setSingleton(boolean singleton) 
{
	                         	 
		this.singleton = 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).