Java

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 Java ecosistema desde lo más básico, abre muchas oportunidades 

Portable

Fácil 

Segura 

Omnipresente 

5 de los mas usados

oop 

Librerías y frameWorks 

Java 8, la base más solida 

Versiones de java, ha evolucionado y se usa java 7 en algunas empresas en java 8 hay nuevas configuraciones y funcionalidades y java 9 y 10 mas avanzado 

JVM escribir en java 

Librerías

Nos da un JRE  es el enviroment para ejecutar programas y es para usuarios comunes 

JDK  para programadores java developmet kit 

Tools para escribir código en java para Bytecode  

cmd java 

 "C:\Program Files\Java\jdk-18.0.1.1\bin"

el JDK es el ambiente para ejecutar aplicaciones Java y ademas posse varias herramientas de desarrollo 

El JRE es el ambiente para ejecutar una aplicacion en java 

JDK = JRE + Herramientas de desarrollo 

Java virtual machine, ejecuta el byetcode 

El JRE nuestro ambiente de ejecución contiene la JVM pero también posee varias librerías incluidas. es decir, para ejecutar una aplicacion java se necesita JVM, y otras librerias 

JRE + JVM = Librerias 

Escribir código en java 

public class ejemplo{

  public static void main(string [] args ) {


System.out.printIn("Hola mundo"):

   }

}

Workspace es un directorio en el cual se guarda o administran los proyectos para mejor organizacion 

Varuables primitivas 

Int para numeros en java maximo 32 bits maximo 

Double 

Long soporta 64 bits maximo

long prueba = 122222222222222222;

 short numeroPequeno = 13555;

byte numeroAunMasPequeno = 8 bytes se usa para procesamiento de archivos de texto 

Float soporta decimales pero es mas pequeño que double 2.5F

Ser explicito al declarar las variables 

Char para palabra en java 1 caracter 

String es lo mas comun para escribir en java 

Sysout + ctrl space 

format ctrl f 

Boolean = true or false;

|| or 

&& and 

Ciclo while 

Incrementar 1 
contador ++;

Ciclo for 

Ciclos anexados 
tabla de multiplicacion 








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