Error: cannot resolve symbol

Are they in seperate packages (directories)? This looks like a failure to import the package PuntoI and Punto are in.

Similarly, it could be a classpath issue.

Since they're all in the same package, they need to be in the same directory, but it sounds like you've got that much correct.

That directory needs to have same name as the package. Make sure the directory and package name match.

Then make sure your classpath (either the CLASSPATH environment variable, or in the -classpath parameter) includes the parent directory of that directory.

So if your files are in, for example, the C:\myjava\estructures directory, make sure your classpath includes C:\myjava and your package declarations are all "package estructures;"

Sorry, I haven't written al the lines the compiler shows me about the error.
Here they are:

--jGRASP exec: javac -g D:\Universidad\2_Edi\2005-2006\estructuras\Punto2Di.java

Punto2Di.java:1: package estructuras does not exist
import estructuras.PuntoI;
^
Punto2Di.java:13: cannot access PuntoI
bad class file: .\PuntoI.class
class file contains wrong class: estructuras.PuntoI
Please remove or make sure it appears in the correct subdirectory of the classpath.
public class Punto2Di implements PuntoI
^
2 errors

Help me please.
Thanks a lot

Hello again :WAVE:

I've done changes following your suggestions.
I have a folder called 'estructuras' which has three files:
Punto.java
PuntoI.java (interface)
Punto2Di.java (implementation)

When I compile 'Punto2Di.java' outside 'estructuras' folder:

--jGRASP exec: javac -g D:\Universidad\2_Edi\2005-2006\Punto2Di.java

Punto2Di.java:13: cannot access estructuras.PuntoI
bad class file: .\estructuras\PuntoI.class
class file contains wrong class: PuntoI
Please remove or make sure it appears in the correct subdirectory of the classpath.
public class Punto2Di implements PuntoI
^
1 error

--jGRASP wedge2: exit code for process is 1.
--jGRASP: operation complete.

And when I compile 'Punto2Di.java' inside 'estructuras' folder:

--jGRASP exec: javac -g D:\Universidad\2_Edi\2005-2006\estructuras\Punto2Di.java

Punto2Di.java:1: package estructuras does not exist
import estructuras.*;
^
Punto2Di.java:13: Punto2Di is not abstract and does not override abstract method Distancia(PuntoI) in PuntoI
public class Punto2Di implements PuntoI
^
Punto2Di.java:22: construir(double,double) in Punto2Di cannot implement construir(double,double) in PuntoI; attempting to use incompatible return type
found : Punto
required: void
public Punto construir(double X, double Y)
^
Punto2Di.java:24: cannot resolve symbol
symbol : method Punto (double,double)
location: class Punto2Di
Punto(X,Y);
^
Punto2Di.java:47: cannot resolve symbol
symbol : method Abcisa ()
location: class Punto
distancia = ( Math.pow((abcisa - puntoAux.Abcisa()),2)
^
Punto2Di.java:48: cannot resolve symbol
symbol : method Ordenada ()
location: class Punto
+ Math.pow((ordenada - puntoAux.Ordenada()),2) );
^
6 errors

--jGRASP wedge2: exit code for process is 1.
--jGRASP: operation complete.

Long ago I tried to set my PATH and CLASSPATH for compiling from the command line wherever in my hard disk. As I didn't achieve it I downloaded jGrasp because I can compile files in other folders than ...\bin

Thanks a lot. :D