This isn't accurate either. Java does not enforce 1 file = 1 public class but rather 1 file = 1 public top-level class.

For example this is totally legit:

  // ClassA.java
  public class ClassA {

    public static class ClassA_Inner_Public_Static {

    }

    public class ClassA_Inner_Public {

    }

  }

  // ClassB.java
  public class ClassB {

    ClassA classa = new ClassA();
    ClassA_Inner_Public classA_Inner_Public = new ClassA().new ClassA_Inner_Public();
    ClassA_Inner_Public_Static classA_Inner_Public_Static = new ClassA_Inner_Public_Static();

  }