Multiple classes in single file

Question

I'm having trouble putting multiple classes into a single file. For example, when my file looks like:

public class FirstClass() {}
public class SecondClass() {}
public class ThirdClass() {}

I get an error during compilation. I'm not quite sure what's causing this. Any ideas?

Answer 1

One Java file can consist of multiple classes with the restriction that only one of them can be public. As soon as you remove public keyword from your classes, you can combine them into a single Java file.