public class Department {

         private Integer id;

         private String name;

         private String description;

....

}

int,double等在Java中都用包装类，因为mysql中的所有类型都可能是NULL，而Java只有引用数据类型才有NULL值

public class Employee {

         private Integer eid;

         private String ename;

         private String tel;

         private String gender;//mysql中用char,在Java中也要用String

         private Double salary;

         private Double commissionPct;

         private Date birthday;//此处用String或Date

         private Date hiredate;

         private Integer jobId;

         private String email;

         private Integer mid;

         private String address;

         private String nativePlace;

         private Integer did;

...

}