Csci Week 3 Notes

Front 1

to use the Scanner class what must you put

Back 1

import java.util.Scanner;
at the top of your source code file

Front 2

To create an instance of the Scanner class to read from the keyboard

Back 2

Scanner myScanner = new Scanner(System.in);

Front 3

For scanner- To read an int value and assign it to a variable

Back 3

int myVariable = myScanner.nextInt();

(call nextInt() )

Front 4

Sorting a list, finding the optimal route between cities, cracking a code, etc

Back 4

algorithm

Front 5

a set of instructions for solving a particular problem.

Back 5

algorithm

Front 6

Without the guarantee with an algorithm

Back 6

it does not constitute an algorithim- called a procedure

Front 7

When finished creating the program (and while creating it), it should be

Back 7

tested with several values (extreme cases)

Front 8

is an often overlooked but crucial step in the software development cycle.

Back 8

Testing

Front 9

a variable with a fixed value

Back 9

named constants

Front 10

public static final Type Variable = Constant;

Back 10

named constants

Front 11

named constants are what when declared

Back 11

initialized

Front 12

used to name named constants

Back 12

uppercase letters

Front 13

use named constants rather than what

Back 13

raw values

Front 14

when do you define constants

Back 14

at the begining of the program

Front 15

If a literal value is used in a program, changing it’s value requires but named constants are what

Back 15

changing every occurrence in the program.

its value can be changed simply by changing the declaration

Front 16

used to represent sequences (i.e., strings) of characters

Back 16

the class String

Front 17

n a program text beginning and ending with "..." is

Back 17

a string constant

Front 18

It is a sequence of characters, but Like other constants, it’s treated as a single item

Back 18

a string constant

Front 19

A string can be what

Back 19

empty: ""

Front 20

A variable declared to be of type String can store what

Back 20

a string constant

Front 21

string is what

string objects are what

Back 21

String is a class.

Its instances are String objects

Front 22

If no value is assigned to a String variable, it has what value

Back 22

null

Front 23

In a method, The variable can’t be used in a print statement until what

Back 23

a value has been assigned

Front 24

The + operator can be used to what two or more strings together (or string objects and other types of values)

Back 24

concatenate

Front 25

String constants and variables can be what

Back 25

mixed

Front 26

string + other types of values the result of the operation is what

Back 26

always a String

Front 27

A String object stores what
and Unlike a primitive value, the sequence can be

Back 27

a sequence of values,
of varying length

Front 28

The String class defines what that can be what

Back 28

several methods that can be invoked (called)

Front 29

returns the number of characters in a particular String object.

Back 29

The length() method

Front 30

the method length () returns what

Back 30

an int

Front 31

You can use a call to method length() when

Back 31

anywhere an int can be used

Front 32

A String is a sequence of character, Each character has what

Back 32

an index (its position)

Front 33

positions start with what number

Back 33

0 (not 1)

Front 34

a portion of the sequence of characters

Back 34

substring

Front 35

returns the character at Index in this string. Index numbers begin at 0

Back 35

charAt(Index)

Front 36

Each String object is what

Back 36

immutable (Once created, its text is fixed), however you can change the value of a String variable and new strings can be created from old

Front 37

used to tell the compiler that the quotation marks (") do not signal the start or end of a string.

Back 37

escape character (\")

("\"Java\" blah blah.")

Front 38

escape character= new line- go to the begining of the next line

Back 38

\n

Front 39

escape character- carriage return- go to the begining of the current line

Back 39

\r

Front 40

escape character- tab- add whitespace up to the next tab stop

Back 40

\t

Front 41

Each escape sequence constitutes what even though it is what

Back 41

a single character

typed with 2 symbols

Front 42

The Unicode character set includes

Back 42

characters from many
different alphabets.

Front 43

breaking String constants across multiple lines does what

Back 43

causes an error

Front 44

can be used to split strings
useful when everything does not fit on one line in the program.

Back 44

The concatenation operator (+)

Front 45

reads the remainder of the current line, even if it is empty

Back 45

nextLine()

Front 46

Often, programs are what to respond to new requirements

Back 46

modified over time

Front 47

Programs which are what are easy to modify.

Back 47

easy to read and understand

Front 48

Even if the program will be used only once

Back 48

you must read it in order to debug it

Front 49

A variable's name should do what

Back 49

suggest its use

Front 50

The best programs are what

Back 50

self-documenting (Clean style
and Well-chosen names)

Front 51

are written into a program as needed explain the program

are used to programs to document the code

Back 51

Comments

Front 52

Comments are useful to who, but they are ignored by who

Back 52

programer

compiler

Front 53

a single line comment begins with what

Back 53

//

Front 54

is ignored by the compiler in a comment

Back 54

Everything after the // to the end of the line

everything in between the multiline comment

Front 55

A multiline comment begins and ends with

Back 55

begins with /*

ends with */

Front 56

begins with /** and ends with */

Back 56

A javadoc comment

Front 57

are used in the comment to describe aspects of the program

Back 57

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