错误：在编译具有多个类的 .Java 文件后使用 Java 命令时无法找到或加载主类

Question

I try to run the java command after compiling my .java file, the .java file contains multiple classes but only one public class and only one main method in the public class. It can't find the main class when all the .class files are in the same place. On netbeans it runs perfectly, on CMD is where the error appears. Also sorry if I make any mistakes in my writing, English isn't my main language, it is Spanish. Thats also why the classes and variables names are in Spanish.

I already checked that the class only have one main method, all the classes are on the same place and there is only one public class in the .java file

That is the code and as you can see only one public class and main is in public class.

    package dfutreras_arqapp_aa19_2b;
   public class Dfutreras_ArqApp_AA19_2B {

    public static void main(String[] args) {
        // TODO code application logic here
        Constructora constructora = new Constructora();
        ConstruyeCasas constructor_SencillaCasa = new ConstruyeCasasSencillas();
        ConstruyeCasas constructor_FamiliarCasa = new ConstruyeCasasFamiliares();

        constructora.setConstruyeCasas(constructor_SencillaCasa);
        constructora.construirCasa();

        Casa casa =  constructora.getCasa();
        System.out.println("Se ha construido una casa " + casa.getTipo());
        System.out.println("Con " + casa.getHabitaciones()+ " habitaciones");
        System.out.println("Con " + casa.getBanos()+ " baños");
        System.out.println("Con " + casa.getVentanas()+ " ventanas");
        System.out.println();
        constructora.setConstruyeCasas(constructor_FamiliarCasa);
        constructora.construirCasa();

        Casa casa2 =  constructora.getCasa();
        System.out.println("Se ha construido una casa " + casa2.getTipo());
        System.out.println("Con " + casa2.getHabitaciones()+ " habitaciones");
        System.out.println("Con " + casa2.getBanos()+ " baños");
        System.out.println("Con " + casa2.getVentanas()+ " ventanas");

    }


    }

//Clase producto

`class Casa{`

    private Integer habitaciones;
    private Integer banos;
    private Integer ventanas;
    private String tipo;

    public void setHabitaciones(Integer habitaciones){
        this.habitaciones = habitaciones;
    }    

    public void setBanos(Integer banos){
        this.banos = banos;
    }

    public void setVentanas(Integer ventanas){
        this.ventanas = ventanas;
    }

    public void setTipo(String tipo){
        this.tipo = tipo;
    }

    public Integer getHabitaciones(){
        return habitaciones;
    }

    public Integer getBanos(){
        return banos;
    }

    public Integer getVentanas(){
        return ventanas;
    }

    public String getTipo(){
        return tipo;
    }
}

//Clase Abstract Builder

abstract class ConstruyeCasas{
  protected Casa casa;`

    public Casa getCasa(){
        return casa;
    }

    public void crearNuevaCasa(){
        casa = new Casa();
    }

    public abstract void constuirHabitaciones();
    public abstract void construirBanos();
    public abstract void construirVentanas();
    public abstract void asignarTipo();
}

//Clase construye casas sencillas

  class ConstruyeCasasSencillas extends ConstruyeCasas{

        @Override
        public void constuirHabitaciones(){
            casa.setHabitaciones(1);
        }
        @Override
        public void construirBanos(){
            casa.setBanos(2);
        }
        @Override
        public void construirVentanas(){
            casa.setVentanas(5);
        }

        @Override
        public void asignarTipo(){
            casa.setTipo("Sencilla");
        }
    }

`//Clase construye casas familiares
`

    class ConstruyeCasasFamiliares extends ConstruyeCasas{
        @Override
        public void constuirHabitaciones(){
            casa.setHabitaciones(3);
        }
        @Override
        public void construirBanos(){
            casa.setBanos(4);
        }
        @Override
        public void construirVentanas(){
            casa.setVentanas(8);
        }

        @Override
        public void asignarTipo(){
            casa.setTipo("Familiar");
        }
    }

//Clase directora

   class Constructora{
        private ConstruyeCasas construyeCasas;

        public void setConstruyeCasas(ConstruyeCasas consCasas){
            construyeCasas = consCasas;
        }


        public Casa getCasa(){
            return construyeCasas.getCasa();
        }

        public void construirCasa(){
            construyeCasas.crearNuevaCasa();
            construyeCasas.constuirHabitaciones();
            construyeCasas.construirBanos();
            construyeCasas.construirVentanas();
            construyeCasas.asignarTipo();

        }
    }

The directory of the .java and the .class files are this:

C:\Users\hecto_000\Documents\NetBeansProjects\Dfutreras_ArqApp_AA19_2B\src\dfutreras_arqapp_aa19_2b

I expect that when I run java Dfutreras_ArqApp_AA19_2B in the CMD after running javac Dfutreras_ArqApp_AA19_2B.java will execute the program and doesn't give me the error: Error Could not find or load the main class Dfutreras_ArqApp_AA19_2B.

Answer 1

Your class is declared as :

package dfutreras_arqapp_aa19_2b;
public class Dfutreras_ArqApp_AA19_2B { 

This means it is in the package dfutreras_arqapp_aa19_2b , and so : - when run the whole package name must be supplied, and - The current directory must be at the root (top-level) directory.

Putting these together means that to run the class, go to the src directory :

C:\Users\hecto_000\Documents\NetBeansProjects\Dfutreras_ArqApp_AA19_2B\src

And run the command:

java dfutreras_arqapp_aa19_2b.Dfutreras_ArqApp_AA19_2B 

To run the class from the current directory, remove the line package dfutreras_arqapp_aa19_2b from the .java file(s), which will mean the class is in the "default" package.

Coincidentally, it is also worth mentioning that Java naming standards are that class names should be "CamelCase" (so without underscores)

Answer 2

在您的所有类中包含 (package dfutreras_arqapp_aa19_2b;) 包，然后尝试一下。