On the History of the Mocha-Java blend:

First we will take a look at the blend's name. Thus far in my research, Mocha-Java appears to be the most accurate name to describe the original blend. Yemeni coffee was traded out of the ancient port of Mocha (English translation). It was purchased by Dutch traders and blended with their own coffee harvests on the island of Java (modern day Indonesia). This was before using regionality to describe origins, so all coffee from the Yemen regions of Moka, Mocca, and Moca were all simply described as "Mocha." Present day blends may be described as Moka-Java (or Mocca, Moca), which is just as correct given that we can trace it to a specific region.