None of the names here are important. In general, the names of the methods, fields, and classes change in each different implementation. What is important is the relationships between the different parts, and the roles each part plays in the whole pattern. You should also note that the entire class is not diagrammed here, only the parts relevant to the pattern.
For instance, it is almost certain that the class has some other methods and fields. If it's an AudioDevice class discussed in the motivation, it probably has some sort of play() methods for example.
However, these are not part of the pattern itself.