类型带反射的文学注入 [英] TypeLiteral injection with reflection
本文介绍了类型带反射的文学注入的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
上下文:使用 guice (最新版本)
Context : java using guice (last version)
大家好,是否可以通过Guice注入一些TypeLiteral:
Hi everybody, is it possible to inject some TypeLiteral with Guice by this way :
public MyClass<?,?> getMyClass(Injector injector, Class<?> a, Class<?> b)
{
//how to Inject MyClass with type a & b ?
//e.g : injector.getInstance(MyClass<"a class","b class">)
}
public interface MyClass<S,T>
{
public T do(S s);
}
public class ClassOne implements MyClass<String,Integer>
{
public Integer do(String s)
{
//do something
}
}
Module :
bind.(new TypeLiteral<MyClass<String,Integer>(){}).to(ClassOne.class);
bind.(new TypeLiteral<MyClass<String,Double>(){}).to(ClassTwo.class);
...
(使用Guice)解决此问题的最佳方法是什么?
What is the best way to handle this problem (with Guice)?
谢谢!
推荐答案
为您的类型创建ParameterizeType:
Create a ParameterizeType for your type :
// It's supposed to be internal.
// You could use sun.reflect.generics.reflectiveObjects but it is not portable.
// Or you can implement it yourself (see below)
ParameterizedType type = new com.google.inject.internal.MoreTypes.ParameterizedTypeImpl(null, MyClass.class, a, b);
从中创建TypeLiteral:
Create a TypeLiteral from it:
TypeLiteral typeLiteral = TypeLiteral.get(type);
现在创建注入的实例:
return (MyClass<A,B>) injector.getInstance(Key.get(typeLiteral))
实际上,您想自己实现ParameteriedType:
In practice you want to implement the ParameteriedType yourself:
final Type[] types = {a, b};
ParameterizedType type = ParameterizedType() {
@Override
public Type[] getActualTypeArguments() {
return types;
}
@Override
public Type getOwnerType() {
return null;
}
@Override
public Type getRawType() {
return MyClass.class;
};
}
实际上,您可以使用:
Types.newParameterizedType(MyClass.class,a,b)
这篇关于类型带反射的文学注入的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
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