Java works in Unicode and therefore string/character JDBC works with Unicode, however a lot of databases use some specific codepage. I know to my sorrow for example, that you select the codepage when you create a PostgreSQL database, and it's immutable thereafter.
So sometimes you may need a little help in character set translation.
However, Eclipse isn't a
word processor, so there are going to be limits on what it will do. You can select a more appropriate code page for a view display - meaning one that maps the characters in question to appropriate display glyphs. But the underlying data will remain the same.