Java之反射机制六：获取方法的泛型信息

public class Test02 {

    public void parameterTest(Map<Integer, Dog> map){

    }

    public Map<Integer,Dog> returnTest(){
        return new HashMap<Integer, Dog>();
    }
}

    @Test  //获取方法的参数中的泛型信息
    public void test() throws NoSuchMethodException {
        Method method = Test02.class.getMethod("parameterTest", Map.class);
        //获取方法的参数类型
        Type[] genericParameterTypes = method.getGenericParameterTypes();
        for (Type genericParameterType : genericParameterTypes) {
            System.out.println("type:"+genericParameterType);
            //ParameterizedType:表示一种参数化类型，比如Collection<Object>
            if(genericParameterType instanceof ParameterizedType){
                Type[] actualTypeArguments = ((ParameterizedType) genericParameterType).getActualTypeArguments();
                for (Type parameterType : actualTypeArguments) {
                    System.out.println(parameterType);
                }
            }
        }
    }

    @Test //获取方法的返回值中的泛型信息
    public void test2() throws NoSuchMethodException {
        Method method = Test02.class.getMethod("returnTest");
        //获取方法的返回值类型
        Type genericReturnType = method.getGenericReturnType();
        if(genericReturnType instanceof ParameterizedType){
            Type[] actualTypeArguments = ((ParameterizedType) genericReturnType).getActualTypeArguments();
            for (Type parameterType : actualTypeArguments) {
                System.out.println(parameterType);
            }
        }
    }