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ximplementation

Ximplementation is an invocation routing framework based on Java annotations.

It has two core annotations:

• @Implementor
  This annotation is annotated on class, indicating that the class is an implementation of some classes, just as the implements and extends keywords.

• @Implement
  This annotation is annotated on method in @Implementor class, indicating that the method is an implement method, just as the @Overriden annotation.

Example

Suppose there is an interface:

	public interface Service<T extends Number>
	{
		T plus(T a, T b);
		T minus(T a, T b);
	}

You can write its implementation in a very free and different way:

	public class ServiceImplDefault<T extends Number> implements Service<T>
	{
		public T plus(T a, T b){...}
		public T minus(T a, T b){...}
	}
	
	public class ServiceImplPlusInteger implements Service<Integer>
	{
		@Override
		public Integer plus(Integer a, Integer b){...}
		
		@NotImplement
		@Override
		public Integer minus(Integer a, Integer b){ throw new UnsupportedOperationException(); }
	}
	
	@Implementor(Service.class)
	public class ServiceImplMinusInteger
	{
		@Implement
		public Integer minus(Integer a, Integer b){...}
	}
	

The ServiceImplMinusInteger is not necessary if you don't want.
And, you can write more than one implementations for plus and/or minus methods in the same class or other @Implementor classes.

Then, you can get a Service instance by:

	Implementation<Service> implementation = new ImplementationResolver().resolve(Service.class,
			 	ServiceImplDefault.class, ServiceImplPlusInteger.class, ServiceImplMinusInteger.class);
	
	ImplementorBeanFactory implementorBeanFactory = SimpleImplementorBeanFactory
				.valueOf(new ServiceImplDefault<Number>(), new ServiceImplPlusInteger(), new ServiceImplMinusInteger());
	
	Service<Number> service = new ProxyImplementeeBeanBuilder().build(implementation, implementorBeanFactory);

The serivce.plus method invocation will be delegated to ServiceImplPlusInteger.plus method if the parameter type is Integer, to ServiceImplDefault.plus method otherwise; and the serivce.minus method will be delegated to ServiceImplMinusInteger.minus method if the parameter type is Integer, to ServiceImplDefault.minus method otherwise.