Re: Support Map<String, String> & Map<String, MyString>
On 10/6/11 2:07 PM, albert kao wrote:
On Oct 6, 4:23 pm, Daniel Pitts<newsgroup.nos...@virtualinfinity.net>
wrote:
On 10/6/11 1:02 PM, Lew wrote:> albert kao wrote:
The following programs work but I like to combine MyComboBox&
MyComboBox2 into one class so that both Map<String, String> &
Map<String, MyString> data types are supported in the single combined
class.
How to do that?
Have 'MyString' implement 'CharSequence' and use a 'Map<String,CharSequence>'?
Or, if you don't really care about the value type, use Map<String, ?> as
the parameter type.
public class MyComboBox {
public MyComboBox(Map<String, ?> data) {...};
}
If you *do* care about the type, then make your ComboBox generic:
public class MyComboBox<V> {
public MyComboBox(Map<String, V> data) {...};
}
public class MyComboBox extends LangComboBox implements
PropertyChangeListener {
protected EventListenerList listenerList = new EventListenerList();
private Set keySet = Collections.EMPTY_SET;
DO NOT USE RAW TYPES!
Seconded.
Inside the MyComboBox constructor, is there a way to figure out
whether the type of value of the Map is String or MyString?
Not really, due to type erasure. It might be helpful if you explain
*why* you need the two constructors. What do they do differently?
Perhaps you're trying to fit a square peg into a round hole. What does
MyString provide that String doesn't?
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