how to compile and run java package program

1package animals;
2/* File name : MammalInt.java */
3public class MammalInt implements Animal {
4   public void eat() {
5      System.out.println("Mammal eats");
6   }
7   public void travel() {
8      System.out.println("Mammal travels");
9   }
10   public int noOfLegs() {
11      return 0;
12   }
13   public static void main(String args[]) {
14      MammalInt m = new MammalInt();
15      m.eat();
16      m.travel();
17   }
18}

1/* File name : Animal.java */
2package animals;
3interface Animal {
4   public void eat();
5   public void travel();
6}