Cosc 1P02 2019 Review

Front 1

Bit

Back 1

Fundamental unit in a computer, stores 1 or 0

Hint 1

Stores 1 or 0

Front 2

Byte

Back 2

Group of 8 bits

Front 3

Syntax

Back 3

Grammatical rules of a programming language

Hint 3

Ex. In Java you always end a statement with a ;

Front 4

High–level language

Back 4

A programming language that is defined by syntax understood by human

Hint 4

What humans can understand

Front 5

Low-level language

Back 5

The language which can be directly understood/executed by the computer

Hint 5

What computers understand

Front 6

Complier

Back 6

A compiler is a program that translates high-level language to low-level language. It translateshuman-written code into computer code (a sequence of zeros and ones)

Hint 6

Takes human code and makes the computer understand it

Front 7

Library

Back 7

A library is a collection of previously compiled code that can be used in future. For example,BasicIO is a library written by someone which we are using now

Hint 7

Written code you can use

Ex. turtle

Front 8

Application Programming Interface (API)

Back 8

A description of the resources (classes and methods) providedby a library

Hint 8

Says what a library can do

Front 9

Package

Back 9

A collection of classes within a Java program. For example, we use a package when dealing withmultiple classes

Front 10

Global/Instance variables

Back 10

Variables defined at the class level and are accessible anywhere in the class

Front 11

Scope (of a variable)

Back 11

The visibility of the variable (the region where a variable is accessible). For example, a global variable is visible/accessible anywhere is the class

Hint 11

Things can only be used in certain areas

Front 12

Method

Back 12

A component of a Java class which contains some code. It represents a functionality/behaviourof the class

Front 13

Cascading method call

Back 13

Chain method calling (in a single line)

Ex. pic.getPixel(0, 0).getColor();

Front 14

Main class

Back 14

A Java class that includes the main method. The flow of execution of any Java program starts at the main method. All main classes have this...

Ex. public static void main(String[] args){...}

Front 15

Constructor

Back 15

A special method which has the same name as the class name. It gets executed automaticallywhen an object is initialized

Front 16

Formal parameter

Back 16

The variable name and type defined in method declaration. Ex. public void multiply(int x, int y){...}

Hint 16

when you call a method

Front 17

Actual parameter

Back 17

The values inserted when calling a method. Ex. multiply(7, 3);

Hint 17

what the method recives

Front 18

Value parameter

Back 18

The value of the variable is copied over to the formal parameter, i.e., passing the valuenot the variable itself.

Ex.

num1 = 5;

int num2 = 8;

multiply ( num1 , num2 ) ;

// equivalent to multiply (5 , 8); we are creatinga copy of the values of num1 and num2 and passing them . We passthe values , not the variables

Front 19

Object

Back 19

Something that has states (characteristics) and behaviours (functionalities). States are the instance/global variables whereas behaviour refers to the methods of the class. For example, the statesof a Turtle are direction, pen state and current coordinate on canvas. Some of the behaviours includepenUp, penDown, forward, backward, etc.

Front 20

Coupling

Back 20

How much do we know about a class. Can be tight or loose

Front 21

Loose coupling

Back 21

A class having sufficient privacy

Hint 21

Ex. uses (private) a lot

Front 22

Tight coupling

Back 22

Not having lots of privacy

Hint 22

Ex. uses (public) a lot

Front 23

Encapsulation

Back 23

Allows for information hiding to reduce (coupling) of classes. Thisis done by the usage of private keyword for instance variables and methods. Other classes can accessthem using accessor and updater methods (getSomething(), setSomething(...)).

Front 24

Abstraction

Back 24

The approach of thinking about the overall/broad idea not the details

Front 25

Procedural abstraction

Back 25

The details of performing an action are abstracted.Used in multiple or one method.

Front 26

Data abstraction

Back 26

Used in multiple classes, The details of state and implementation of behaviour are abstracted.

Front 27

Object-Oriented language

Back 27

A programming language that allows the concept of objects (i.e., abstractionand encapsulation). For example, Java is an object-oriented programming language. Everything in Java is an object.

Front 28

Private

Back 28

A keyword in Java which indicates a variable or method to be private. This means that otherclasses cannot access them (encapsulation/information hiding)

Front 29

Casting

Back 29

A way to change the type of a variable. In Java, it is written by writing the desired type inparentheses in front of the value. For example, int x = (int) 3.14;

Front 30

Implicit type conversion

Back 30

A type conversion (cast) which is done automatically by Java. For example:

double x = 10;

//it automatically becomes 10.0

Front 31

Narrowing conversion

Back 31

The process in which a type is down cast to another type usually losing precision.For example, converting a double to int

Front 32

Collection

Back 32

An object which holds sub-objects, i.e., Picture holds Pixels, Sound holds Samples

Front 33

Garabage collection

Back 33

A way for Java to reclaim memory which is not used anymore

Front 34

Reference Variable

Back 34

A variable which represents an object or an address in memory rather than a value.

Front 35

End of File (EOF)

Back 35

End Of File is the condition (state) that become true when an attempt is made to read data fromthe file but no further data available to be read

Front 36

Algorithm

Back 36

A well-defined sequence of steps to solve a problem (the recipe of a program).

Front 37

Switch statement

Back 37

A more compact way of if, else if, else if, · · ·, else if, else statements. Itaccepts a value and checks the possible cases

Front 38

Persistent object

Back 38

Extending an object’s lifetime so that it is written to hard drive and will not vanishafter the program closes

Front 39

serialVersionUID

Back 39

A constant that may be specified for a Serializable (persistent) object. It specifies aunique key that differentiates objects of this class from objects of other classes that have been writtento hard drive. The compiler can verify that the object read is of the correct type and version

Front 40

Garbage collection

Back 40

The process of discovering unused memory and clearing it for reuse

Front 41

In-test Loop

Back 41

A loop in which its condition is neither the first operation in the loop, nor the last. It iswithin the loop. This means that the statements of the loop body are in two parts: the part beforethe condition which is executed 1 or more times and the part after the condition which is executed 0or more times. There is no in-test loop in Java but we can build one using an if statement:

while ( true ) {

// the part before the condition , runs once at least

if( file . isEOF () ) {

//in - loop condition

break ;}

// the part after the condition , possible to run zero times .

}