Java Class.cast() vs. cast operator

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I’ve only ever used Class.cast(Object) to avoid warnings in “generics land”. I often see methods doing things like this:

@SuppressWarnings("unchecked")
<T> T doSomething() {
    Object o;
    // snip
    return (T) o;
}

It’s often best to replace it by:

<T> T doSomething(Class<T> cls) {
    Object o;
    // snip
    return cls.cast(o);
}

That’s the only use case for Class.cast(Object) I’ve ever come across.

Regarding compiler warnings: I suspect that Class.cast(Object) isn’t special to the compiler. It could be optimized when used statically (i.e. Foo.class.cast(o) rather than cls.cast(o)) but I’ve never seen anybody using it – which makes the effort of building this optimization into the compiler somewhat worthless.

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