The current JDK uses two constructors for Date —the void constructor that is
intended to be the “now constructor," and a constructor that takes a number of
milliseconds since epoch.
In this chapter, we've met several different classes of data. Textual and numeric data
are the most obvious examples, but as working programmers we will meet a large
number of different sorts of data. Let's move on to look at whole files of data, and
new ways to work with I/O and networking. Fortunately, Java provides good sup‐
port for dealing with many of these abstractions.