Self-Review Exercises

1.1 Fill in the blanks in each of the following statements:

a) In 2007, the _____________ was formed to develop, maintain and evolve Android, driving innovation in mobile technology and improving the user experience while reducing costs.

b) The _____________ Plugin for Eclipse allows you to create, run and debug Android apps, and export them for distribution.

c) Multitouch screens allow you to control your Android device with _____________ involving one touch or multiple simultaneous touches.

d) With web services, you can create _____________, which enable you to rapidly develop apps by quickly combining complementary web services, often from different organizations and possibly other forms of information feeds.

e) Android uses a collection of _____________, which are named groups of related, predefined classes.

f) The _____________, included in the Android SDK, allows you to run Android apps in a simulated environment within Windows, Mac OS X or Linux.

g) Almost any noun can be reasonably represented as a software object in terms of _____________ (e.g., name, color and size) and behaviors (e.g., calculating, moving and communicating).

h) A program unit called a(n) _____________ houses the methods that perform its tasks.

i) You send messages to an object. Each message is a(n) _____________ that tells a method of the object to perform its task.

1.2 State whether each of the following is true or false. If false, explain why.

a) One benefit of developing Android apps is that the operating system is proprietary to Google.

b) The openness of the Android platform discourages innovation.

c) You can reuse a class many times to build many objects. Reuse of existing classes when building new classes and programs saves time and effort.

d) Attributes are specified by the class’s methods.

e) Objects may communicate with one another, but they’re normally not allowed to know how other objects are implemented—implementation details are hidden within the objects themselves.

1.3 Fill in the blanks in each of the following statements (based on Section 1.8):

a) Objects have the property of _____________—although objects communicate with one another, they’re normally not allowed to know how other objects are implemented.

b) The _____________ that objects come from are essentially reusable software components; they include attributes and behaviors.

c) The process of analyzing and designing a system from an object-oriented point of view is called _____________.

d) With _____________, new classes of objects are derived by absorbing characteristics of existing classes, then adding unique characteristics of their own.

e) The size, shape, color and weight of an object are considered _____________ of the object’s class.

f) A class that represents a bank account might contain one _____________ to deposit money to an account, another to withdraw money from an account and a third to inquire what the account’s current balance is.

g) You must build an object of a class before a program can perform the tasks that the class’s methods define—this process is called _____________.

h) The balance of a bank account class is an example of a(n) _____________ of that class.

i) Your project’s requirements define what the system is supposed to do and your design specifies _____________ the system should do it.