additional javadoc and tests

org.springframework.context/src/main/java/org/springframework/context/support/ConversionServiceFactoryBean.java

@@ -71,6 +71,9 @@ public class ConversionServiceFactoryBean implements FactoryBean<ConversionServi
 	
 	/**
 	 * Creates the ConversionService instance returned by this factory bean.
+	 * Creates a default conversion service instance by default.
+	 * Subclasses may override to customize the ConversionService instance that gets created.
+	 * @see ConversionServiceFactory#createDefaultConversionService()
 	 */
 	protected ConversionService createConversionService() {
 		return ConversionServiceFactory.createDefaultConversionService();

org.springframework.context/src/main/java/org/springframework/format/support/FormattingConversionServiceFactoryBean.java

@@ -60,6 +60,10 @@ public class FormattingConversionServiceFactoryBean implements FactoryBean<Conve
 
 	// subclassing hooks 
 	
+	/**
+	 * Install Formatters and Converters into the new FormattingConversionService using the FormatterRegistry SPI.
+	 * Subclasses may override to customize the set of formatters and/or converters that are installed.
+	 */
 	protected void installFormatters(FormatterRegistry registry) {
 		registry.addFormatterForFieldType(Number.class, new NumberFormatter());
 		registry.addFormatterForFieldAnnotation(new NumberFormatAnnotationFormatterFactory());