只需将两个文件放在同一目录中即可。这是一个例子：
人.java
public class Person { public String name; public Person(String name) { this.name = name; } public String toString() { return name; }}学生.java
public class Student extends Person { public String somethingnew; public Student(String name) { super(name); somethingnew = "surprise!"; } public String toString() { return super.toString() + "t" + somethingnew; } public static void main(String[] args) { Person you = new Person("foo"); Student me = new Student("boo"); System.out.println("Your name is " + you); System.out.println("My name is " + me); }}运行Student（因为它具有主要功能）会为我们带来所需的结果：
Your name is fooMy name is boo surprise!
