Java泛型-构造函数调用的显式类型参数

Question

I believe I can provide explicit type arguments for the class while invoking constructor with new operator, like this:

MyClass<?> obj = new MyClass<Float>("test", 1);

where MyClass is defined like this:

class MyClass<T>{
    <K, V> MyClass(K k, V v){        
}

I suppose in this case Float is assigned to type parameter T. And for K & V compiler infers the type from actual arguments provided.

My doubt is how I can provide explicit type arguments for constructor? I know for methods I can do like obj.method<Integer, String>(1, "test");

I wonder is this kind of explicit type arguments(for K&V; not for T) are possible with constructors.

Hoping somebody can clear this for me. Thanks in advance.

Answer 1

You give type arguments between new and class name:

MyClass<?> obj = new <String, Integer>MyClass<Float>("test", 1);

BTW, for methods you give type argument before method name:

obj.<Integer, String>method(1, "test");