Granny's Programming Pearls
"inside of every large program is a small program struggling to get out"
JavaRanch.com/granny.jsp
The moose likes Beginning Java and the fly likes Typecaste confusion Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login


Win a copy of OCA/OCP Java SE 7 Programmer I & II Study Guide this week in the OCPJP forum!
JavaRanch » Java Forums » Java » Beginning Java
Bookmark "Typecaste confusion" Watch "Typecaste confusion" New topic
Author

Typecaste confusion

Saurabh Pillai
Ranch Hand

Joined: Sep 12, 2008
Posts: 509

I can call first method like save(myCustomObject); but when I call saveAll(myCustomObjects), (myCustomObjects is List<MyCustomObject>) it gives me compilation error.
.
Why?
Stephan van Hulst
Bartender

Joined: Sep 20, 2010
Posts: 3647
    
  17

Because List<SubType> is not a subtype of List<Type>.

Instead, your method declaration should probably look like:
Read more about it in Oracle's Java Tutorials, the Generics trail.
Saurabh Pillai
Ranch Hand

Joined: Sep 12, 2008
Posts: 509
Thank you Stephan.
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: Typecaste confusion