It is a bad practice to use Sun's proprietary Java classes?

Question

The compiler display warnings if you use Sun\'s proprietary Java classes. I\'m of the opinion that it\'s generally a bad idea to use these classes. I read this somewhere. Ho

Answer 1

Yes, because nobody guarantees that these classes or API will be the same with the next Java release and I bet it's not guaranteed that those classes are available in Java versions from other vendors.

So you couple your code to special Java version and loose at least portability.