//JAVA
//1-MAIN METHOD A program must have this:
public static void main(String[] args) {
System.out.println("Java Resources For Coding");
System.out.println("See Packages and Classes");
}
//2-METHODS
//VOID: no devuelve nada
public void metodo1(){System.out.println("El metodo imprime esto");}
//NO-VOID Hay que indicar el tipo de variable que se devuelve y debe haber un return
public int metodo2(){return 1;}
//STATIC VS NON STATIC
// Static method - Static methods can be called without creating objects, example main method
static void myStaticMethod() { System.out.println("Static methods can be called without creating objects");}
// Public method - must be called by creating objects
public void myPublicMethod() {System.out.println("Public methods must be called by creating objects");}
//MODIFIERS
//Classes:
//final: The class cannot be inherited by other classe
//abstract: The class cannot be used to create objects (To access an abstract class, it must be inherited from another class)
//Atributes and methods
//final: cannot be override modified
//abstract: Can only be used in an abstract class, and can only be used on metho
//static: Attributes and methods belongs to the class, rather than an object
//transient
//synchronized
//volatile
//TYPES OF VARIABLES
public void TypesOfVariables(){
// private int number = 2;
// public String nombre = "Tyler";
// protected double decimal = 23.90;
//3-PUBLIC PRIVATE PROTECTED DEFAULT: they need to be created outside the method, in the object
//PUBLIC: The code is accessible for all classes, from everywhere
//PRIVATE: The code is only accessible within the declared class
//PROTECTED: The code is accessible in the same package and subclasses.
//DEFAULT: The code is only accessible in the same package. This is used when you don't specify a modifier.
}
//4-TYPES OF VARIABLES
public void Variables(){
String cadena = "Hola";
char sexo = 'M'; //Stores a single character/letter or ASCII values
int numero = 1923;
float decimal = 12.000f;
double decimal2 = 12.8000;
boolean boleano = true; //true, false
//WHOLE NUMBERS
byte diasem = 1; //Stores whole numbers from -128 to 127
short diaanual = 300; //Stores whole numbers from -32,768 to 32,767
long miliseg = 1298332800000L; //Stores whole numbers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
//FRACTIONAL NUMBERS
float decimal3 = 12.000f; //Stores fractional numbers. Sufficient for storing 6 to 7 decimal digits
double decimal4 = 12.8000; //Stores fractional numbers. Sufficient for storing 15 decimal digits
}
//5-SCANNER Method
public void Scanner(){
float c1, c2, x;
Scanner teclado = new Scanner (System.in); //Import needed !
System.out.print("Introduce el primer numero C1: ");
c1 = teclado.nextInt();
System.out.print("Introduce el segundo numero C2: ");
c2 = teclado.nextInt();
//Operation:
x = -(c2) / c1;
System.out.println("El valor de x es: "+x);
}
//6-FORMATTING
public void Formatting(){
//Escape characters
// \' = '
// \" = "
// \\ = \
// \n New Line
// \r Carriage Return
// \t Tab
// \b Backspace
// \f Form Feed
short x = 7; //deberia ser tipo byte
int y = 5; //deberia ser tipo byte
float f1 = 13.5f; //le falta la f al final 13.5f
float f2 = 8f;
System.out.println("El valor de x es " + x + " y el valor de y es "+ y);
System.out.println("El resultado de x + y es " + (x + y));
System.out.println("El resultado de x - y es " + (x - y));
System.out.printf("%s\n %s %s\n","División entera:","x / y = ",(x/y));
System.out.println("Resto de la división entera: x % y = " + (x % y));
System.out.printf("El valor de f1 es %f y el de f2 es %f\n",f1,f2);
System.out.println("El resultado de f1 / f2 es " + (f1 / f2));
//System.out.printf("Tu edad es: %s años, %s meses y %s días", periodo.getYears(), periodo.getMonths(), periodo.getDays());
//7-TRY/CATCH: Se utiliza para controlar errores
public void tryCatch(){
Scanner num = new Scanner (System.in);
int x;
try {
x = num.nextInt();
if (x >=1 && x <= 100){
boolean ver = false;
// num.nextLine();
}
else {
System.out.println(x + " No es uno de esos números.");
}
}catch (Exception ex){
// num.nextLine();
System.out.print("No es correcto. "+ex);
}
}
//TIPO ENUMERADO
class TipoEnumerado {
public enum Meses {
Enero, Febrero, Marzo, Abril, Mayo, Junio,
Julio, Agosto, Septiembre, Octubre, Noviembre, Diciembre};
public void Enumerado(enum Meses){
Meses m = Meses.Marzo;
System.out.println("El mes actual es " + m);
String eme = "Abril"; //Marzo
m = Meses.valueOf(eme);
System.out.println("El mes actual es " + m);
}
}
