Java简单表的映射练习

/*EMP-Dept 简单表的映射
 *简单一对一
 */
class Dept{//部门信息类
    private int deptno;
    private String dname;
    private String loc;
    private Emp[] emps;
    public void setEmps(Emp[] emps){
       this.emps = emps;
    }
    public Emp[] getEmps(){
       return this.emps;
    }
    public Dept(int deptno,String dname,String loc){
       this.deptno = deptno;
       this.dname = dname;
       this.loc = loc;
    }
    public String getInfo(){
       return "部门编号："+this.deptno+"，部门名称："+this.dname+"，部门位置："+this.loc;
    }
}

class Emp{//雇员信息类
    private int empno;
    private String ename;
    private String job;
    private double sal;
    private double comm;
    private Dept deptno;
    private Emp mgr;
    public void setDeptno(Dept deptno){
       this.deptno = deptno;
    }
    public Dept getDeptno(){
       return this.deptno;
    }
    public void setMgr(Emp mgr){
       this.mgr = mgr;
    }
    public Emp getMgr(){
       return this.mgr = mgr;
    }
    public Emp(int empno,String ename,String job,double sal,double comm){
       this.empno = empno;
       this.ename = ename;
       this.job = job;
       this.sal = sal;
       this.comm = comm;
    }
    public String getMgrInfo(){//扩充一个取得领导信息的方法
       return "领导编号："+this.empno+"，雇员名字："+this.ename+"，职位："+this.job+"，工资："+this.sal+"，佣金："+this.comm;
    }
    public String getInfo(){
       return "雇员编号："+this.empno+"，雇员名字："+this.ename+"，职位："+this.job+"，工资："+this.sal+"，佣金："+this.comm;
    }
}入代码

public class DeptEmpTest{
   public static void main(String[] args){
       Dept dept = new Dept(18,"ACCOUNTANT","CHIAN");
       Emp ea = new Emp(1,"SMITH","CHERK",250,0.0);
       Emp eb = new Emp(2,"FROD","MANAGER",250,0.0);
       Emp ec = new Emp(3,"KING","PRESIDENT",250,0.0);
       //设置雇员-领导关系
       ea.setMgr(eb);
       eb.setMgr(ec);
       //设置雇员-部门关系
       ea.setDeptno(dept);
       eb.setDeptno(dept);
       ec.setDeptno(dept);
       //设置部门-雇员关系
       dept.setEmps(new Emp[] {ea,eb,ec});

       System.out.println(ea.getInfo());
       System.out.println("\t|-"+ea.getMgr().getMgrInfo());
       System.out.println("++++++++++++++++++++++++++++++++++++++++++++++++++++++");
       for(int x=0; x<dept.getEmps().length;x++){
       System.out.println(dept.getEmps()[x].getInfo());
          if(dept.getEmps()[x].getMgr() != null){
             System.out.println("\t|-"+dept.getEmps()[x].getMgr().getMgrInfo());
          }
       }

    }
}