CIS 123 Midterm

programming language, platform

What aspects does Java technology contain?

bytecode

What source files in Java are compiled to

Java Virtual Machine

Device Java uses in order to operate their code on multiple systems

API

A large collection of ready-made software components that provide many useful capabilities

package

Libraries of related classes and interfaces in which APIs are grouped

C++

The language in which Java is majorly derived from

platform independence

achieved by compiling the Java language code "halfway" to bytecode

automatic memory management model

the Garbage collection

references

what do candidate objects for the garbage collection lack

requirements, design, code, test

The waterfall development steps

inception, elaboration, construction, transition

The unified process steps

inception

unified phase in which the system is still being felt out to determine the scope of the system

elaboration

unified phase in which people are trying to mitigate the architectural risks of the system

construction

unified phase in which people are finishing all of the relevant use cases to make the system production ready/beta ready

transition

unified phase in which people move the system through its final release stages and beta releases, possibly including operations and maintenance

eXtreme Programming

Development methodology that focuses on the endless cycle of coding, creating, feedback, and remake

one

How many public classes can a file have?

public

What kind of file requires a name that matches the class name?

non-public, inner

What kind of classes can be in the same file?

built-in primitives

data that is stored directly in memory locations associated with the variable

boolean

primitive data type which stores true or false values

byte

primitive data type which holds integer in 8 bits

char

primitive data type which holds a single character

short, int, long

order of primitive data integer sizes from smallest to largest

float, double

primitive data type which holds real numbers

name, type location in memory, value

the four features of variables

implicit conversion

data type conversion from smaller type to larger

explicit conversion

data type conversion from larger to smaller

adapter

design pattern used to help an existing class conform to a new interface

adapter

design pattern which wraps the old class to work with the new interface

model-view-controller

design pattern which isolates display code from program flow and the business model

model-view-controller

design pattern which makes it possible for new views to be snapped on to existing logic

command

design pattern which allows a common front end to execute commands that it doesn't know ahead of time

command

design pattern which can add new orders even during runtime

strategy

design pattern which allows algorithms in for a particular task

strategy

design pattern which can represent different roles the object is taking or different environments

composite

design pattern which allows multiple objects of the same type ot be treated as one

composite

design pattern which is an example of using the inheritance loops

conditional statement

lets us choose which statement will be executed, give the power to make basic decisions

short-circuited operators

what type of operator is it if the left operand is sufficient to determine the result and the right operand is not evaluated

ternary

a conditional operator that requires three operands

Tolerance

What operating tactic should be used in comparing two floating point values

unicode

The character set in which Java character data is based on

iterator

an object that allows you to process a collection of items one at a time

hasNext, next

the two methods that every iterator object possesses

exception

a representation of an error condition or a situation that is not the expected result of a method, isolate the code that deals with the error condition from regular program logic

checked, unchecked

two categories of exceptions

checked

type of exceptions which are inherited from the core Java class Exception, represent non fatal to program executions

unchecked

type of exceptions which are considered fatal, will terminate the program with an appropriate error message

try-catch

the mechanism which is used to trigger an exception and handle the exception

finally

an optional block that when written, will always be executed, either after the "try" block code or after the "catch" block code

throws

a method declaration that says that the coder will be handling the exception himself

immutable

most important quality of the String class

length()

method that returns the number of characters contained in the string object

toString()

method that converts a non-string object to a String

printf()

method that is used to specify output formats

format specifiers

placeholders with format info

valueOf()

method that converts a string to an object of one of the primitive numeric types

charAt()

method used to get a certain character within a string

substring()

method that produces more than one consecutive character from a string

StringBuffer, StringBuilder

classes that allow character changes to Strings

String Tokenizer

Used to break a string into meaningful tokens

method library

contains useful static methods

create a program, create a method library, define new data

the uses for a class

instance data, instance method, class or methods

What is necessary for defining a new data type

constructors

What is the only aspect that classes do not inherit from parent classes

arguments

what does the system-supplied constructor not take

cannot be accessed

What happens to the system supplied constructor when it is overridden

super()

method used to access the parent constructor

this()

method used to access other defined constructors

instance

data-wise, variables that has variables that each individual class object will contain its own copy of and its own value for

instance

method-wise, called with a class object and may operate directly on instance data members

class members

An alternate way to say "static"

static

data-wise, variables that are shared by all objects in a class, only one ultimate copy exists

static

method-wise, stand-alone method that does not need any instance members to do its job

yes

yes

yes

yes

public

everywhere in program

in a subclass

in rest of package

in rest of class

no

yes

yes

yes

protected

everywhere in program

in a subclass

in rest of package

in rest of class

no

no

yes

yes

default case (no keyword)

everywhere in program

in a subclass

in rest of package

in rest of class

no

no

no

yes

private

everywhere in program

in a subclass

in rest of package

in rest of class

static

var: belongs to class

meth: class method

class: promotes to outer class

final

var: forever constant

meth: cannot be overriden

class: cannot be subclassed

void

meth: no return type

native

meth: implemented in non Java

class: contains a native method

abstract

class used to embody a design and partial code, cannot be instantiated

interface

contains no bodies or variables, can implement as desired

object

base of all other classes

toString(), equals(), clone()

the methods an object class always contains

classes

Java nouns are...

functions

Java verbs are...

public

how should member functions be declared

private

how should member data be declared

java file

used to declare a class

driver program

written to test the class as completely as possible

method

in charge of any changes to the object's state

self-governing

necessary trait for any object

encapsulation

hiding implementation details of an object from its clients

abstraction

separation of external view from internal view

public

an object's data should never be declared this

public visibility

used to declare methods that provide the object's services

service methods

alternate name for public methods