How to get type arguments class of generic method parameter? [duplicate]

Answer 1

I think you can't do that. Check out this class:

public class TestClass
{
    private List list = new ArrayList();

    /**
     * @param args
     * @throws NoSuchFieldException
     * @throws SecurityException
     */
    public static void main(String[] args)
    {
        try
        {
            new TestClass().getClass().getDeclaredField("list").getGenericType(); // this is the type parameter passed to List
        }
        catch (SecurityException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        catch (NoSuchFieldException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        new TestClass(). insert(new ArrayList());
    }

    public  void insert(List tList)
    {
        ParameterizedType paramType;
        paramType = (ParameterizedType) tList.getClass().getGenericInterfaces()[0];
        paramType.getActualTypeArguments()[0].getClass();
    }
}

You can get the type parameters from a class or a field but it is not working for generic methods. Try using a non-generic method!

OR

another solution might be passing the actual Class object to the method.