Knowing type of generic in Java

Question

I have a generic class, says :

MyClass

Inside a method of this class, I would like to test the type of T, for example :

Answer 1

You can't, normally, due to type erasure. See Angelika Langer's Java Generics FAQ for more details.

What you can do is pass a Class into your constructor, and then check that:

public MyClass
{
    private final Class clazz;

    public MyClass(Class clazz)
    {
        this.clazz = clazz;
    }

    public void myMethod()
    {
        if (clazz == String.class)
        {
           ...
        }
    }
}

Note that Java does not allow primitives to be used for type arguments though, so int is out...