e.g.
public interface CacheClient
{
List<?> getKeysWithExpiryCheck();
}
Or should I return
List<Object>
e.g. public interface CacheClient { List<?> getKeysWithExpiryCheck(); } Or should I return List<Object>
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e.g.
public interface CacheClient
{
List<?> getKeysWithExpiryCheck();
}
Or should I return
List<Object>
Here is a good intro to Java Generics. [A] and [B] explain the difference between ? and Object. Basically, ? indicates that the type is unknown which is a problem if you need to add items to the list. However, if you only read from the list it is OK to treat the result as an Object. Although, I suggest to use some thing like
[A] http://java.sun.com/docs/books/tutorial/extra/generics/subtype.html
[B] http://java.sun.com/docs/books/tutorial/extra/generics/wildcards.html