Why did i get this error?

here's the code:

class Acount
{ int sum ; String owner ; //these seem to make sense 
    //a constructor or two 
    public Acount () 
    { this.sum = 0 ; this.owner = "John Doe" ; }

    public Acount (String name) 
    {this.sum = 0 ; this.owner = name ; } 

    public Acount (String name, int sum) 
    {this.sum = sum ; this.owner = name ; } 

    //prints an acount in the format "owner" "sum" 
    public static void printAcount (Acount Acount) 
    {System.out.print (Acount.owner) ; System.out.print (" ") ; System.out.println (Acount.sum) ; } 

    public static void main (String[]arg) 
    { 
        Acount Acount1 = new Acount ("david", 100) ; 
        System.out.println ("heres the first acount as it was created:") ; 
        printAcount (Acount1) ; 
        System.out.println ("now i changed one of its instance varaibles with a static method") ; 开发者_运维百科
        upOne (Acount1) ; 
        printAcount (Acount1) ; 
    } 

    public static Acount upOne (Acount Acount)
    { 
        Acount.sum = Acount.sum + 1 ; 
        return Acount ; 
    } 
}

here's the error:

Exception in thread "main" java.lang.NoClassDefFoundError: Acount/java

What went wrong and why?

How did you run the Java program in the command line, is it like this?

java Account.java

If yes, the remove the .java, because the java command takes a class name, not the file. The correct command is:

java Account

Also, make sure you compiled the file properly.

It has to do with the way you are calling your class from the commandline. You shouldnt put the .java after your class name. try:

java -classpath . Account

That error represents an error in your command line. Try

 java Acount

Not java Acount.java