131Chapter 5
Introduction to Java:
Objects, Methods,
Classes, and Interfaces
The programming language used for developing your Android applications is Oracle’s Java SE,
which was created by Sun Microsystems and acquired by Oracle. As you learned in Chapter 1, Java
SE stands for Java Standard Edition, though many programmers shorten this to just “Java” to refer
to this programming language.
Java is what is called an object-oriented programming (OOP) language, which you are going
to learn all about during this chapter. It is important to note that all of these Java programming
concepts, components, and constructs that you will be learning during this “Java Primer” chapter
will apply equally well to both the 32-bit Android 4.4 OS as well as to the new 64-bit Android 5.0 OS
that will be released by the end of 2014.
OOP is based on the concept of developing modular, self-contained constructs that are called
“objects.” These OOP constructs contain their own attributes and characteristics. In this chapter,
you will learn a great deal about the OOP characteristics of Java, and the logic behind using a
modular programming approach and OOP techniques to build applications that are easy to share
and debug due to an OOP approach.
You will also learn about all of the other Java programming language constructs, such as packages
and classes, methods and interfaces, loops and arrays, variables and constants, and application
programming interfaces (APIs), which tie everything together into one coherent computing ecosystem,
such as the 19 Android Java Platform APIs, which were discussed in Chapter 2. Android’s 19 APIs are
actually progressive collections of all of these Java programming constructs. The 64-bit Android 5.0
OS is the 20th API, and will be covered in Chapter 16, “The Future of Android.”