Old Brown Java is a name used for a deliberately matured Java coffee style. The source describes green beans changing from their usual greenish appearance toward a light brown color during treatment. That description concerns the unroasted material; it should not be confused with the color chosen by a roaster when preparing the finished coffee for brewing.
Ask how the seller’s particular lot was treated and how that history is documented. A reference to monsooning or aging does not tell you the exact conditions or make every batch equivalent. Likewise, older accounts of a process lasting several years should not be copied onto a current product unless the producer or supplier confirms its own treatment.
When choosing a roast, consider the intended brewing method and the roaster’s experience with that lot. Compare the brewed body, aroma and acidity with a conventional coffee rather than judging from the green-bean color alone. Deliberate maturation and careless storage are not interchangeable ideas. The name is a reason to ask more precise questions, without assuming that a brown appearance establishes quality or that this article reports a personal tasting of the product.
The conversation
A good question can make a better brew.