Employee.java

/*
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/**
 *
 * @author adas
 */
final public class Employee extends Person {
    
}

Person.java

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/**
 *
 * @author adas
 */
public class Person {
    private transient long	createTime;
    public Person(){
        createTime = System.currentTimeMillis();
    }

    public long getCreateTime() {
        return createTime;
    }

    @Override
    public String toString() {
        return getClass() + "[createTime=" + createTime + ']';
    }
    
}

Student.java

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/**
 *
 * @author adas
 */
final public class Student extends Person {
    
}

TS11.java

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/**
 *
 * @author adas
 */
public class TS11 {
    public static void main(String[] args) {
        Employee e1 = new Employee();
        Person p1 = new Person();
        Student s1 = new Student();
        System.out.println((Object) e1);
        System.out.println((Object) p1);
        System.out.println((Object) s1);
    }
}