c10n

Class C10NFilters

java.lang.Object

c10n.C10NFilters

public final class C10NFilters
extends Object

Author:

rodion

Constructor Summary

Constructors

Constructor and Description
C10NFilters()

Method Summary

Methods

Modifier and Type	Method and Description
static <T> C10NFilterProvider<T>	cachedFilterProvider(C10NFilterProvider<T> filterProvider) Decorates the specified filter provider with a simple static cache.
static <E extends Enum<?>> C10NFilterProvider<E>	enumMapping(Class<E> enumClass, Class<?> c10nMappedInterface) Create an Enum-to-methods mapping filter to ease Enum translation using C10N.
static <T> C10NFilterProvider<T>	staticFilterProvider(C10NFilter<T> filter) Filter provider that always returns the specified instance

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

C10NFilters

public C10NFilters()

Method Detail

enumMapping

public static <E extends Enum<?>> C10NFilterProvider<E> enumMapping(Class<E> enumClass,
                                                    Class<?> c10nMappedInterface)

Create an Enum-to-methods mapping filter to ease Enum translation using C10N.

Basic Usage

Consider the following Enum type with 3 values:

   enum Status{
     Open, Closed, Pending
   }
 

In order to localise each of the values, first create a c10n interface with a method for each of the Status values

   @C10NMessages
   public interface StatusMsg {
     @En("open")
     @Ja("未着手")
     String open();
 

     @En("closed! beer time!")
     @Ja("完了")
     String closed();
 

     @En("pending ...")
     @Ja("進行中")
     String pending();
   }
 

Then, in your c10n configuration add an enum-filter binding for the Status type

   void configure(){
     bindFilter(C10NFilters.enumMapping(Status.class, StatusMsg.class), Status.class);
   }
 

Now, every time c10n encounters Status as a method argument in a c10n-interface type, the it will be replaced with the appropriate localised version of the Enum value:

   @C10NMessages
   public interface Messages{
     @En("Localised status is: {0}")
     @Ja("状態は{0}")
     String showStatus(Status status);
   }
 

Invoking showStatus(Status.Closed) will render as "Localised status is: closed! beer time!".

Restricting Filter Application

You can restrict filter application only to method arguments annotated with a given annotation, or one of the given annotations from a list, by using annotatedWith(Class) method when binding. For example:

   void configure(){
     bindFilter(new IntFormattingFilter(), int.class)
       .annotatedWith(Precise.class);
   }
 

The above declaration will make sure int arguments are only passed through the IntFormattingFilter whenever the method argument is marked with the @Precise annotation. Other int arguments will not have the filter applied.

Method Mapping Rules

Enum values are mapped to c10n-interface methods in the following order:

1. Method name matches "<Enum class name>_<Enum value name>". e.g status_open()
2. Method name matches "<Enum value name>" e.g. closed()

Note: method mapping is case-insensitive.

Note: mapped methods cannot take any arguments. Methods with arguments will be excluded from mapping.

Warning: if mapping for one or more values is not found, a runtime exception will be thrown.

Type Parameters:

E - Enum type

Parameters:

enumClass - Enum type to create mapping for

c10nMappedInterface - a c10n-interface containing mapped methods

Returns:

a non-cached provider of enum mapping filter

staticFilterProvider

public static <T> C10NFilterProvider<T> staticFilterProvider(C10NFilter<T> filter)

Filter provider that always returns the specified instance

Type Parameters:

T - Filter argument type

Parameters:

filter - filter instance to return from the generated provider(not-null)

Returns:

instance of filter provider (never-null)

cachedFilterProvider

public static <T> C10NFilterProvider<T> cachedFilterProvider(C10NFilterProvider<T> filterProvider)

Decorates the specified filter provider with a simple static cache. Only the first call will result in an execution of C10NFilterProvider.get() method. The following calls will always return a cached instance of the first call.

Type Parameters:

T - Filter argument type

Parameters:

filterProvider - filter provider to decorate with caching (not-null)

Returns:

instance of a filter provider decorated with simple static cache (never-null)