Chapter 1-2

Question 1

Define hardware

Answer 1

physical devices that you see on your desktop

Question 2

define software

Answer 2

programs that give the hardware useful functionality

Question 3

name the two types of software

Answer 3

system software and application software

Question 4

What is a user interface, and what’s an example of one

Answer 4

it supports moment to moment communication between the user and the computer: like a keyboard and mouse

Question 5

what is an example of an auxiliary input output device

Answer 5

printers and scanners

Question 6

what are auxiliary storage devices, and what’s an example of one

Answer 6

it’s basically secondary memory. examples would be hard disks, CD ROMS, and flash memory sticks

Question 7

network connection

Answer 7

so, connection to the internet, with routers and modems

Question 8

what is internal memory?

Answer 8

it is RAM (which is random access memory or primary memory). it’s fast and relatively small

Question 9

what is a central processing unit?

Answer 9

it performs the work on a computer, consists of billions of transistors

Question 10

what is a bit?

Answer 10

smallest unit of information. processed by a computer

Question 11

what is a byte?

Answer 11

8 adjacent bits

Question 12

what is a byte’s location in memory called?

Answer 12

its’ address

Question 13

how would you look at the software development process

Answer 13

through the waterfall method

Question 14

name the steps of the waterfall method

Answer 14

1. customer request 2. analysis 3. design 4. implementation 5. integration 6. maintenance

Question 15

what’s mnemonic device you can use for the waterfall method

Answer 15

CADIIM

Question 16

which phase is the most expensive in the waterfall method

Answer 16

maintenance

Question 17

what is encapsulation

Answer 17

combining the description of resources and behaviors in a single software entity

Question 18

what is inheritance

Answer 18

the hierarchical class structure and sharing of instance variables and methods with subclasses

Question 19

what is polymorphism

Answer 19

different types of objects can understand the same message.

Question 20

true or false: an object’s response to a message does NOT depend on the object’s class

Answer 20

false. an object’s response to a message DOES depend on the object’s class

Question 21

what is information hiding

Answer 21

it’s providing access to services, but not to data resources.

Question 22

true or false: classes are organized in a hierarchy

Answer 22

true. classes are organized in a hierarchy

Question 23

what does a root class do

Answer 23

it defines methods and instance variables shared by its subclasses.

Question 24

what do subclasses do

Answer 24

they define additional methods and instance variables

Question 25

what type of language is java?

Answer 25

it is a modern object oriented language.

Question 26

why is java secure? (think about construction)

Answer 26

it is secure because it enables construction of virus free, tamper free systems

Question 27

why is java robust? (think about development)

Answer 27

it is robust because it supports development of programs that do not overwrite memory

Question 28

why is java portable? (think about how it runs)

Answer 28

it is portable because it can be run on different types of computers without change

Question 29

true or false: java supports threads

Answer 29

true! java does supports threads!! it’s a process that can run concurrently with other processes

Question 30

Java resembles ___.

Answer 30

java resembles C++. it’s easy for C++ programmers to learn Java

Question 31

what are the weaknesses of Java?

Answer 31

it’s slow and it’s prone to viruses because it’s commonly used

Question 32

what is a java virtual machine?

Answer 32

the java compiler translates Java source code into java byte code

Question 33

what is byte code

Answer 33

it’s pseudo machine language, executed by the JVM

Question 34

what is an interpreter

Answer 34

a program that behaves like a computer

Question 35

why is a virtual machine great?

Answer 35

basically: all machines use a different machine language - before you’d have to write a program that could only run on one type of machine.. if you wanted to run it somewhere else, you’d have to rewrite the program. now, you can write once, run everywhere

Question 36

what are java applets?

Answer 36

java programs that run in a Web browser. a JVM is incorporated into the browser

Question 37

two types of user interface style:

Answer 37

graphical user interface (program interacts with users via windows with graphical components) and terminal input output interface (programs interact with users via a command terminal)

Question 38

what is a program

Answer 38

it’s a sequence of instructions that perform a task

Question 39

what is source code

Answer 39

the programming language instructions for a program

Question 40

what is the file extension type for a java source code file?

Answer 40

.java

Question 41

what is the file extension type for a java class file?

Answer 41

.class

Question 42

what are the steps to make a java program?

Answer 42

1. edit the .java file 2. compiling turns .java file into .class file 3. execute the program

Question 43

what does the import statement do

Answer 43

allows us to use classes that other programmers have written. it also tells the java compiler where to find specifications for the class

Question 44

what should we use when writing source code?

Answer 44

use a text editor, integrated development environment (we use BlueJ which detects syntax errors)

Question 45

the main factor affecting readability is ______.

Answer 45

layout

Question 46

true or false, the compiler does not ignore layout

Answer 46

false. the compiler DOES ignore layout

Question 47

why is it important for you code to be readable by others?

Answer 47

because it may be maintained by others