class name and file name should be same??

Hi All,
I am having two public classes in a file like this:
public class A
{
// Class body
}
public class B extends A
{
// Class body
public static void main(String args[])
{
// Function body
}
}
When I compile its giving the following error:
B.java:1: class A is public, should be declared in a file named A.java
Why it is so.Whats wrong in this.

Thanks in advance,
Jana.

Jawahar M,
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Thanks Pardner! Hope to see you 'round the Ranch!
[ September 11, 2002: Message edited by: Dirk Schreckmann ]

The Java compiler only allows one public class definition per file. The file name must match the name of the public class definition contained in the file (if a public class definition exists in the file). So, if you were to do as the error message suggested, your problem would likely be solved.
This construct allows the compiler to easily figure out what to do with a source file and the class file definitions. In other languages, such as C, it is my understanding that these rules are not enforced and so, when compiling, the programmer must also provide a make file that tells the compiler what to do. I may have understood that incorrectly as I've never programmed in C.

Originally posted by Dirk Schreckmann:
In other languages, such as C, it is my understanding that these rules are not enforced and so, when compiling, the programmer must also provide a make file that tells the compiler what to do.

Yep, that's pretty much it.