如何将类型安全的对象强制转换为 JComboBox<String> ?

Question

I have this code:

@Override
public void itemStateChanged(ItemEvent evt) {
    if (evt.getStateChange() == ItemEvent.SELECTED) {
        Object sourceObject = evt.getSource();

        if (sourceObject instanceof JComboBox<?>) {
            JComboBox<String> jComboBox = (JComboBox<String>) sourceObject;
        }
    }
}

What is the best and correct casting for generics type safety and avoiding suppress the warning?

Answer 1

You nailed it. Runtime instanceof checks don't check generic parameters so the way you have shown it is the standard way that it is done.