Expresiones y Tipos

8/3/2019 Expresiones y Tipos

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Fundamentos de programacinFundamentos de programacin

Una vista a los principios deprogramacin

TopicosTopicos Panorama Proceso de desarrollo de un programa

Palabras reservadas, tipos, salida


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RevistasRevistas

ByteByte www.mkmwww.mkm--pi.compi.com

PC ActualPC Actualhttp://www.pcactual.com/http://www.pcactual.com/

PC Magazine www.pcmag.comPC Magazine www.pcmag.com

Linux Magazine www.linuxLinux Magazine www.linux--mag.commag.com

2 Fundamentos

PCPC WorldWorldwww.pcworld.comwww.pcworld.com JavaJava ProProwww.javawww.java--pro.compro.com


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3 Fundamentos


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Reglas bsicasReglas bsicas

Elementos del lenguajeElementos del lenguaje


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5 FundamentosEl lenguaje de programacin

Java

5


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Palabras Reservadas (Keywords)Palabras Reservadas (Keywords)

6 Fundamentos

true, false, null ?

Palabras claves tienen significado

especial y no pueden usarse como

identificadores de variables ni

clases ni mtodos


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Como trabaja JavaComo trabaja Java

7 Fundamentos


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Qu hars con JavaQu hars con Java

8 Fundamentos

Esto no es un tutorial esEsto no es un tutorial esEsto no es un tutorial esEsto no es un tutorial es

solo una ilustracinsolo una ilustracinsolo una ilustracinsolo una ilustracin


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Anatoma de una clase en JavaAnatoma de una clase en Java

9 FundamentosEl lenguaje de programacin

Java

9


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Anatoma de una clase en JavaAnatoma de una clase en Java

/*

* File: HelloWorld.java

* Author: Java Java Java

* Description: Prints Hello World greeting.

*/

public class HelloWorld extends Object // Class header

{ // Start class body

private String greeting = "Hello World!";

Comments

10 Fundamentos

{ // Start method bodySystem.out.println(greeting); // Output statement

} // greet() // End method body

public static void main(String args[]) // Method header

{

HelloWorld helloworld; // declare

helloworld = new HelloWorld(); // create

helloworld.greet(); // Method call

} // main()

} // HelloWorld class // End class body


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CommentsComments

comment: A note written in source code by thecomment: A note written in source code by theprogrammer to describe or clarify the code.programmer to describe or clarify the code.

Comments are not executed when your program runs.

Syntax:Syntax:

11 Fundamentos

or,or,/*/* comment text; may span multiple linescomment text; may span multiple lines */*/

Examples:Examples:// This is a one-line comment.

/* This is a very long

multi-line comment. */


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Using commentsUsing comments

Where to place comments:Where to place comments:

at the top of each file (a "comment header")

at the start of every method (seen later) to explain complex pieces of code

12 Fundamentos

Comments are useful for:Comments are useful for:

Understanding larger, more complex programs.

Multiple programmers working together, who mustunderstand each other's code.


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Using commentsUsing comments

/* This first comment begins and ends on the same line.

*/

/* A second comment starts on this line ...and goes on ...

and this is the last line of the second comment.

*/

*

13 Fundamentos

/* This is NOT a fourth comment. It is justpart of the third comment.

And this is the last line of the third comment.

*/

*/ This is an error because it is an unmatched end

marker.


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El punto de partida: mainEl punto de partida: main

14 Fundamentos


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Que puedo poner dentro del

main

Que puedo poner dentro del

main Dentro del mtodo main como cualquier otro mtodoDentro del mtodo main como cualquier otro mtodopueden agregarsepueden agregarse Declaraciones

Asignaciones

Condiciones

Re eticiones o ciclos

15 Fundamentos

Selecciones

Rompimientos

Invocaciones a otros metodos

Retornos

Etc


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Salida mediante printlnSalida mediante println

Cualquier tipo primitivo oCualquier tipo primitivo o StringString

Pueden lograrse resultados semejantes al usarPueden lograrse resultados semejantes al usar printprint

Se usan caracteres de escape para caracteres noSe usan caracteres de escape para caracteres noimprimibles o ambiguosimprimibles o ambiguos

16 Fundamentos

Ya estamos usando paquetes, objeto, mtodos,Ya estamos usando paquetes, objeto, mtodos,parmetrosparmetros


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System.out.printlnSystem.out.println

A statement that prints a line of output on theA statement that prints a line of output on theconsole.console.

pronounced "print-linn" sometimes called a "println statement" for short

17 Fundamentos

Two ways to useTwo ways to use System.out.printlnSystem.out.println ::

System.out.println("text");

Prints the given message as output.

System.out.println();

Prints a blank line of output.


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Names and identifiersNames and identifiers

You must give your program a name.You must give your program a name.public class SerHumano {

Naming convention: capitalize each word (e.g.MyClassName)

Your program's file must match exactly (SerHumano.java)

"

18 Fundamentos

-sensitive")

identifieridentifier: A name given to an item in your program.: A name given to an item in your program. must start with a letter or_ or $

subsequent characters can be any of those or a number

legal: _myName TheCure ANSWER_IS_42 $bling$

illegal: me+u 49ers side-swipe Ph.D's


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SyntaxSyntax

syntax: The set of legal structures and commandssyntax: The set of legal structures and commandsthat can be used in a particular language.that can be used in a particular language. Every basic Java statement ends with a semicolon ;

The contents of a class or method occur between { and }

19 Fundamentos

structure of a program that causes the compiler tostructure of a program that causes the compiler tofail.fail. Missing semicolon Too many or too few { } braces

Illegal identifier for class name

Class and file names do not match

...


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Syntax error exampleSyntax error example11 public class Hello {public class Hello {

22 ppooooblic static void main(String[] args) {blic static void main(String[] args) {

33 System.System.owtowt.println("Hello, world!")_.println("Hello, world!")_

44 }}

55 }}

Compiler output:Compiler output:

20 Fundamentos

..

pooblic static void main(String[] args) {pooblic static void main(String[] args) {^Hello.java:Hello.java:33: ';' expected: ';' expected}}^2 errors2 errors

The compiler shows the line number where it found theerror.

The error messages can be tough to understand!


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StringsStrings

string: A sequence of characters to be printed.string: A sequence of characters to be printed. Starts and ends with a " quote " character.

The quotes do not appear in the output. Examples:

"hello"

21 Fundamentos

"This is a string. It's very long!"

Restrictions:Restrictions: May not span multiple lines.

"This is nota legal String."

May not contain a " character.

"This is not a "legal" String either."


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Escape sequencesEscape sequences

escape sequence: A special sequence of charactersescape sequence: A special sequence of charactersused to represent certain special characters in a string.used to represent certain special characters in a string.

\t tab character\n new line character

\" quotation mark character

Otros Caracteres de

Escape

\b \r \

\007 \u0007

22 Fundamentos

Example:System.out.println("\\hello\nhow\tare \"you\"?\\\\");

Output:\hellohow are "you"?\\


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QuestionsQuestions

What is the output of the followingWhat is the output of the followingprintlnprintlnstatements?statements?

System.out.println("\ta\tb\tc");

System.out.println("\\\\");

System.out.println("'");

23 Fundamentos

ys em.ou .pr n n ;

System.out.println("C:\nin\the downward spiral");

Write aWrite aprintlnprintln statement to produce this output:statement to produce this output:

/ \ // \\ /// \\\


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AnswersAnswers

Output of eachOutput of eachprintlnprintln statement:statement:

a b c

\\'

"""

C:

24 Fundamentos

in he downward spiral

printlnprintln statement to produce the line of output:statement to produce the line of output:

System.out.println("/ \\ // \\\\ /// \\\\\\");


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QuestionsQuestions

WhatWhatprintlnprintln statements will generate this output?statements will generate this output?

This program prints a

quote from the Gettysburg Address.

"Four score and seven years ago,our 'fore fathers' brought forth on

"

25 Fundamentos

.

WhatWhatprintlnprintln statements will generate this output?statements will generate this output?

A "quoted" String is'much' better if you learn

the rules of "escape sequences."

Also, "" represents an empty String.Don't forget: use \" instead of " !'' is not the same as "


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AnswersAnswersprintlnprintln statements to generate the output:statements to generate the output:

System.out.println("This program prints a");System.out.println("quote from the GettysburgAddress.");System.out.println();System.out.println("\"Four score and seven yearsago,");

System.out.println("our 'fore fathers' brought forthon");

" ""

26 Fundamentos

. . .

printlnprintln statements to generate the output:statements to generate the output:

System.out.println("A \"quoted\" String is");System.out.println("'much' better if you learn");

System.out.println("the rules of \"escape sequences.\"");System.out.println();System.out.println("Also, \"\" represents an emptyString.");

System.out.println("Don't forget: use \\\" instead of \"!");

System.out.println("'' is not the same as \"");


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27 FundamentosEl lenguaje de programacinJava

27


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28 Fundamentos


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Reglas para identificadoresReglas para identificadores

Nombran variables, funciones, clases y objetosNombran variables, funciones, clases y objetos

Comienza con una letra, un subrayado (_) o unComienza con una letra, un subrayado (_) o unsmbolo de dlar ($). Los siguientes caracteressmbolo de dlar ($). Los siguientes caracterespueden ser letras o dgitos.pueden ser letras o dgitos.

29 Fundamentos

Se distinguen las maysculas de las minsculasSe distinguen las maysculas de las minsculas No hay una longitud mxima establecida para elNo hay una longitud mxima establecida para el

identificador.identificador.


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Data typesData typestype: A category or set of data values.type: A category or set of data values.

Constrains the operations that can be performed on data

Many languages ask the programmer to specify types

Examples: integer, real number, string

30 Fundamentos

Internally, computers store everything as 1s and 0sInternally, computers store everything as 1s and 0s104 01101000

"hi" 01101000110101


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VariablesVariables

Sirven para referirse tanto a objetos como a tiposSirven para referirse tanto a objetos como a tiposprimitivos.primitivos.

Tienen que declararse antes de usarse:Tienen que declararse antes de usarse:tipotipo identificadoridentificador;;

intint osicionosicion

31 Fundamentos

SeSe puedepuede inicializarinicializar mediantemediante unauna asignacinasignacin::tipotipo identificadoridentificador == valorvalor;;

intintposicionposicion == 00;;

DefinicinDefinicin dede constantesconstantes::

staticstatic finalfinal floatfloat PIPI == 33..1415914159ff;;

L i bl ti tiL i bl ti ti


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Las variables tienen un tipo y

nombre

Las variables tienen un tipo y

nombre

El compilador se

quejara, en general

32 Fundamentos

cuando exista

incompatibilidad de

tipos


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Tipos de datos primitivosTipos de datos primitivos

Java maneja 8 tipos primitivos:Java maneja 8 tipos primitivos:byte (entero de 8 bits)

short (entero de 16 bits) int (entero de 32 bits)

lon entero de 64 bits

33 Fundamentos

float (decimal de 32 bits)

double (decimal de 64 bits)

char (Unicode de 16 bits)

boolean (true, false)

Versiones no primitivas

Byte Short

Integer Long

Float Double

Character

Boolean

Boxing y Unboxing


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Tipos de datos primitivosTipos de datos primitivos

34 Fundamentos

Versiones no primitivasByte Short

Integer Long

Float Double

Character

Boolean

Boxing y Unboxing

Tipos primiti os EnterosTipos primiti os Enteros


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Tipos primitivos Enteros y

Flotantes

Tipos primitivos Enteros y

Flotantes

Difieren al entero en

35 Fundamentos

almacenamiento


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Tipos primitivosTipos primitivos

36 Fundamentos36


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Evite derramamientosEvite derramamientos

int x=24;

byte b= x;

El vaso chico no

tiene suficiente

capacidad

37 Fundamentos37


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OperadoresOperadores

Operadores Asociatividad Tipo

() izquierda a derecha parntesis

++ -- + - ! derecha a izquierda unarios

* / % izquierda a derecha multiplicativos

En orden de precedencia:

38 Fundamentos

-

< >= izquierda a derecha relacionales== != izquierda a derecha de igualdad

& izquierda a derecha AND lgico booleano

^ izquierda a derecha OR exclusivo lgico booleano

| izquierda a derecha OR inclusivo lgico booleano

&& izquierda a derecha AND lgico

| | izquierda a derecha OR lgico

?: derecha a izquierda condicional

expresion ? sentencia1 : sentencia2

= += -= *= /= %= derecha a izquierda asignacin ej. x += y x = x + y;


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Precedencia de OperadoresPrecedencia de Operadores

39 Fundamentos



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Precedencia de Operadores

(Cont)


(Cont)

40 Fundamentos



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(Cont)


(Cont)

41 Fundamentos

NOTA:

Precedencias de mayor a menor

LR significa asociatividad de izquierda a derecha

RL de derecha a izquierda


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42 Fundamentos

EXPRESIONESEXPRESIONESOperaciones y precedencia de operadoresOperaciones y precedencia de operadores


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ExpressionsExpressionsexpression: A value or operation that computes aexpression: A value or operation that computes a

value.value.

Examples: 1 + 4 * 5(7 + 2) * 6 / 3

42

43 Fundamentos

The simplest expression is a literal value. A complex expression can use operators and parentheses.


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Arithmetic operatorsArithmetic operatorsoperator: Combines multiple values or expressions.operator: Combines multiple values or expressions.

+ addition

- subtraction (or negation) * multiplication / division

44 Fundamentos

. . .

As a program runs, its expressions areAs a program runs, its expressions are evaluatedevaluated..

1 + 1 evaluates to 2 System.out.println(3 * 4); prints 12

How would we print the text 3 * 4 ?


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Integer division with /Integer division with /When we divide integers, the quotient is also anWhen we divide integers, the quotient is also an

integer.integer. 14 / 4 is 3, not 3.5

45 /10 is 4

52/14 is 4

135 / 27 is 5

45 Fundamentos

MoreMore examples:examples: 32 / 5 is 6

84 / 10 is 8 156 / 100 is 1

Dividing by 0 causes an error when your program runs.


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Integer remainder with %Integer remainder with %TheThe %% operator computes the remainder from integeroperator computes the remainder from integer

division.division. 14 % 4 is 2

218 % 5 is 3

3 43

4 ) 14 5 ) 218

12 20

2 18

15

3

46 Fundamentos

ApplicationsApplications ofof %% operator:operator:

Obtain last digit of a number: 230857 % 10 is 7 Obtain last 4 digits: 658236489 % 10000 is6489

See whether a number is odd: 7 % 2 is 1, 42 % 2 is 0

a s e resu

45 % 6 = ___ 2 % 2=___ 8 % 20=___ 11 % 0=____


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PrecedencePrecedenceprecedence: Order in which operators are evaluated.precedence: Order in which operators are evaluated.

Generally operators evaluate left-to-right.1 - 2 - 3 is (1 - 2) - 3 which is -4

But * / % have a higher level of precedence than + -

1 + 3 * 4 is 13

47 Fundamentos

6 + 8 / 2 * 36 + 4 * 3

6 + 12 is 18

Parentheses can force a certain order of evaluation:(1 + 3) * 4 is 16

Spacing does not affect order of evaluation1+3 * 4-2 is 11


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Precedence examplesPrecedence examples

1 * 2 + 3 * 5 % 41 * 2 + 3 * 5 % 4

\\_/_/||22 + 3 * 5 % 4+ 3 * 5 % 4

1 + 8 % 3 * 2 - 9

\_/|

1 + 2 * 2 - 9

\___/

48 Fundamentos

__

||2 +2 + 1515 % 4% 4

\\___/___/||

2 +2 + 33

\\________/________/||

55

|

1 + 4 - 9 \______/

|5 - 9

\_________/|-4


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Precedence questionsPrecedence questionsWhat values result from the following expressions?What values result from the following expressions?

9 / 5

695 % 20 7 + 6 * 5

7 * 6 + 5

49 Fundamentos

248 % 100 / 5 6 * 3 - 9 / 4

(5 - 7) * 4

6 + (18 % (17 - 12))


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Real numbers (type double)Real numbers (type double)Examples:Examples: 6.0226.022 ,, --42.042.0 ,, 2.143e172.143e17

Placing .0 or . after an integer makes it a double.

The operatorsThe operators ++ -- ** // %% ()() all still work withall still work with doubledouble..

50 Fundamentos

: . . .

Precedence is the same: () before * / % before + -


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Real number exampleReal number example2.0 * 2.4 + 2.25 * 4.0 / 2.02.0 * 2.4 + 2.25 * 4.0 / 2.0

\\___/___/||4.84.8 + 2.25 * 4.0 / 2.0+ 2.25 * 4.0 / 2.0

\\___/___/

51 Fundamentos

4.8 +4.8 + 9.09.0 / 2.0/ 2.0

\\_____/_____/||

4.8 +4.8 + 4.54.5 \\____________/____________/

||

9.39.3

Mixing typesMixing types


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Mixing typesMixing types

WhenWhen intint andand doubledouble are mixed, the result is aare mixed, the result is adoubledouble.. 4.2 * 3 is 12.6

The conversion is perThe conversion is per--operator, affecting only itsoperator, affecting only itsoperands.operands. 2.0 + 10 / 3 * 2.5 - 6 / 4

52 Fundamentos

7 / 3 * 1.2 + 3 / 2 \_/

|2 * 1.2 + 3 / 2

\___/|2.4 + 3 / 2

\_/|

2.4 + 1

\________/|3.4

___|

2.0 + 3 * 2.5 - 6 / 4 \_____/

|2.0 + 7.5 - 6 / 4

\_/|

2.0 + 7.5 - 1 \_________/

|9.5 - 1

\______________/|8.5

S i iS i i


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String concatenationString concatenation string concatenation: Usingstring concatenation: Using ++ between a string andbetween a string and

another value to make a longer string.another value to make a longer string.

"hello" + 42 is "hello42"1 + "abc" + 2 is "1abc2""abc" + 1 + 2 is "abc12"1 + 2 + "abc" is "3abc"

53 Fundamentos

"abc" + 9 * 3 is "abc27""1" + 1 is "11"4 - 1 + "abc" is "3abc"

UseUse ++ to print a string and an expression's valueto print a string and an expression's value

together.together. System.out.println("Grade: " + (95.1 + 71.9) / 2);

Output: Grade: 83.5


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VariablesVariables

54 Fundamentos

Receipt exampleReceipt example


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Receipt exampleReceipt example

What's bad about the following code?What's bad about the following code?public class Receipt {

public static void main(String[] args) {

// Calculate total owed, assuming 8% tax / 15%tipSystem.out.println("Subtotal:");System.out.println(38 + 40 + 30);

" "

55 Fundamentos

. .System.out.println((38 + 40 + 30) * .08);System.out.println("Tip:");System.out.println((38 + 40 + 30) * .15);System.out.println("Total:");System.out.println(38 + 40 + 30 +

(38 + 40 + 30) * .08 +

(38 + 40 + 30) * .15);}

}

The subtotal expression (38 + 40 + 30) is repeated

So manyprintln statements

V i blV i bl


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VariablesVariablesvariable: A piece of the computer's memory that isvariable: A piece of the computer's memory that is

given a name and type, and can store a value.given a name and type, and can store a value. Like preset stations on a car stereo, or cell phone speed dial:

56 Fundamentos

Steps for using a variable:

Declareit - state its name and type

Initializeit - store a value into itUseit - print it or use it as part of an

expression

DeclarationDeclaration


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DeclarationDeclarationvariable declaration:variable declaration: Sets aside memory for storing aSets aside memory for storing a

value.value. Variables must be declared before they can be used.

Syntax:Syntax:

57 Fundamentos

type name;

The name is an identifier.

int x;

double myGPA;

x

myGPA

AssignmentAssignment


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AssignmentAssignmentassignment: Stores a value into a variable.assignment: Stores a value into a variable.

The value can be an expression; the variable stores its result.

Syntax:Syntax:

name = expression;

58 Fundamentos

int x;

x = 3;

double myGPA;myGPA = 1.0 + 2.25;

x 3

myGPA 3.25

Using variablesUsing variables


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Using variablesUsing variablesOnce given a value, a variable can be used inOnce given a value, a variable can be used in

expressions:expressions:

int x;

x = 3;

System.out.println("x is " + x); // x is 3

59 Fundamentos

ys em.ou .pr n n x - ; -

You can assign a value more than once:You can assign a value more than once:

int x;

x = 3;System.out.println(x + " here"); // 3 here

x = 4 + 7;

System.out.println("now x is " + x); // now x is 11

x 3x 11

Declaration/initializationDeclaration/initialization


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Declaration/initializationDeclaration/initializationA variable can be declared/initialized in oneA variable can be declared/initialized in one

statement.statement.

Syntax:Syntax:

60 Fundamentos

type name = value;

double myGPA = 3.95;

int x = (11 % 3) + 12;

x 14

myGPA 3.95

Assignment and algebraAssignment and algebra


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Assignment and algebraAssignment and algebraAssignment usesAssignment uses == , but it is not an algebraic, but it is not an algebraic

equation.equation.

= means, "store the value at right in variable at left"

The ri ht side ex ression is evaluated first

61 Fundamentos

and then its result is stored in the variable atleft.

What happens here?What happens here?int x = 3;

x = x + 2; // ???

x 3x 5

Assignment and typesAssignment and types


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Assignment and typesAssignment and types A variable can only store a value of its own type.A variable can only store a value of its own type.

int x = 2.5; // ERROR: incompatible types

AnAn intint value can be stored in avalue can be stored in a doubledouble variable.variable. The value is converted into the e uivalent real number.

62 Fundamentos

double myGPA = 4;

double avg = 11 / 2;

Why does avg store 5.0and not 5.5 ?

myGPA 4.0

avg 5.0

Compiler errorsCompiler errors


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Compiler errorsCompiler errorsA variable can't be used until it is assigned a value.A variable can't be used until it is assigned a value.

int x;

System.out.println(x); // ERROR: x has no value

YouYou may not declare the same variable twice.may not declare the same variable twice.

63 Fundamentos

int x;int x; // ERROR: x already exists

int x = 3;

int x = 5; // ERROR: x already exists

How can this code be fixed?

Printing a variable's valuePrinting a variable's value


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Printing a variable s valuePrinting a variable s valueUseUse ++ to print a string and a variable's value on oneto print a string and a variable's value on one

line.line.

double grade = (95.1 + 71.9 + 82.6) / 3.0;System.out.println("Your grade was " + grade);

64 Fundamentos

n s u en s = ;

System.out.println("There are " + students +" students in the course.");

Output:

Your grade was 83.2

There are 65 students in the course.

Receipt questionReceipt question


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p qp q

Improve the receipt program using variables.Improve the receipt program using variables.

public class Receipt {public class Receipt {public static void main(String[] args) {public static void main(String[] args) {

// Calculate total owed, assuming 8% tax / 15% tip// Calculate total owed, assuming 8% tax / 15% tipSystem.out.println("Subtotal:");System.out.println("Subtotal:");System.out.println(38 + 40 + 30);System.out.println(38 + 40 + 30);

" "" "

65 Fundamentos

System.out.println((38 + 40 + 30) * .08);System.out.println((38 + 40 + 30) * .08);

System.out.println("Tip:");System.out.println("Tip:");System.out.println((38 + 40 + 30) * .15);System.out.println((38 + 40 + 30) * .15);

System.out.println("Total:");System.out.println("Total:");System.out.println(38 + 40 + 30 +System.out.println(38 + 40 + 30 +

(38 + 40 + 30) * .15 +(38 + 40 + 30) * .15 +(38 + 40 + 30) * .08);(38 + 40 + 30) * .08);}}

}}

Receipt answerReceipt answer


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pppublic class Receipt {public class Receipt {

public static void main(String[] args) {public static void main(String[] args) {// Calculate total owed, assuming 8% tax / 15% tip// Calculate total owed, assuming 8% tax / 15% tipint subtotal = 38 + 40 + 30;int subtotal = 38 + 40 + 30;double tax = subtotal * .08;double tax = subtotal * .08;double tip = subtotal * .15;double tip = subtotal * .15;double total = subtotal + tax + tip;double total = subtotal + tax + tip;

S stem.out. rintln "Subtotal: " + subtotalS stem.out. rintln "Subtotal: " + subtotal

66 Fundamentos

System.out.println("Tax: " + tax);System.out.println("Tax: " + tax);

System.out.println("Tip: " + tip);System.out.println("Tip: " + tip);System.out.println("Total: " + total);System.out.println("Total: " + total);

}}}}

Conversiones implcitas yexplcitasConversiones implcitas yexplcitas


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explcitasexplcitas Conversin ImplcitaConversin Implcita

El compilador realiza una conversin automtica al operando de

mayor precisin

67 Fundamentos

Conversin ExplcitaConversin Explcita Es necesario agregar el cdigo que permita la conversin

Ej. byte b= (byte) variableLong;

fDato= (float)dDato;

Variables referenciaVariables referencia


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Podemos pensar en unavariable de referencia a

un objeto, como uncontrol remoto a eseobjeto, usado para

68 Fundamentos

Creacin de ObjetosCreacin de Objetos


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69 FundamentosEl lenguaje de programacinJava 69


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USO Y CREACIN DEOBJETOSUSO Y CREACIN DEOBJETOS

70 Fundamentos

Uso y creacin de ObjetosUso y creacin de Objetos


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ResumenResumen Se mostrar la forma en que los programas toman su

entrada de datos

Algunas entradas por Parmetros, Teclado y Archivos Utilizaremos la clase String, Scanner, InputStream

representando al data source.

71 Fundamentos

Utilizaremos mtodos, repeticiones, clases, parmetros.

ASCIIASCII


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Cdigo ASCIICdigo ASCII


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73 Fundamentos

Caracteres no imprimiblesCaracteres no imprimibles


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