This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
There are some more advanced techniques using reflection, but they don't add any advantage.
A object-oriented purist would prefer code that centralizes all direct references to das to one accessor method and one mutator method. This allows edits to be added in one place and lets you change the real das to, say, different units of measure without looking at every bit of code that depends on das. It also works better with JavaBeans.