Java - 将double转换为float

Question

I've seen an example where the following code is used to convert a double to a float:

Double.valueOf(someDouble).floatValue()

I would just do it like

(float)someDouble

Is there any advantage to using the former?

Answer 1

Looking at the implementation of Double 's floatValue() :

/**
 * Returns the value of this {@code Double} as a {@code float}
 * after a narrowing primitive conversion.
 *
 * @return  the {@code double} value represented by this object
 *          converted to type {@code float}
 * @jls 5.1.3 Narrowing Primitive Conversions
 * @since JDK1.0
 */
public float floatValue() {
    return (float)value;
}

It looks like it behaves exactly like your casting. Therefore there's no advantage to using it.