Comments on: explain this http://www.sworddance.com/blog/2007/08/13/explain-this/ Tue, 06 Jan 2009 15:38:18 +0000 http://wordpress.org/?v=2.6.5 By: Arman Sharif http://www.sworddance.com/blog/2007/08/13/explain-this/#comment-12433 Arman Sharif Sat, 19 Jan 2008 21:09:25 +0000 http://www.sworddance.com/blog/2007/08/13/explain-this/#comment-12433 I had a similar problem where I also used casting as a workaround. There's another side to this problem though related to autoboxing. For example, if T is an Integer, the following code will compile in eclipse but fail with javac int result = getFoo(); The error message from javac is "type parameters of T cannot be determined; no unique maximal instance exists for type variable T with upper bounds int,java.lang.Object" The only way to get the above code building with both is to give up autoboxing completely: Integer result = getFoo(); This was using Eclipse 3.3.1.1 and java 5 (1.5.0_14-b03). I had a similar problem where I also used casting as a workaround. There’s another side to this problem though related to autoboxing.

For example, if T is an Integer, the following code will compile in eclipse but fail with javac

int result = getFoo();

The error message from javac is “type parameters of T cannot be determined; no unique maximal instance exists for type variable T with upper bounds int,java.lang.Object”

The only way to get the above code building with both is to give up autoboxing completely:

Integer result = getFoo();

This was using Eclipse 3.3.1.1 and java 5 (1.5.0_14-b03).

]]> By: Clemens Renner http://www.sworddance.com/blog/2007/08/13/explain-this/#comment-10907 Clemens Renner Mon, 03 Dec 2007 12:08:09 +0000 http://www.sworddance.com/blog/2007/08/13/explain-this/#comment-10907 Thanks a lot for the post. It saved our day debugging the migration to Maven with a few projects. IMHO this is just another hint at how badly generics have been implemented in Java. Thanks a lot for the post. It saved our day debugging the migration to Maven with a few projects.

IMHO this is just another hint at how badly generics have been implemented in Java.

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