使用类集实现以下数据表和简单Java类的映射实现；

importjava.util.Iterator;
importjava.util.List;
classEmp{//emp表映射类
privateintempno;
privateStringename;
privateStringjob;
privatedoublesal;
privatedoublecomm;
privateEmpmgr;//雇员领导
privateDeptdept;//雇员所属部门
publicEmp(){//无参构造
}
publicEmp(intempno,Stringename,Stringjob,doublesal,doublecomm){
this.empno=empno;
this.ename=ename;
this.job=job;
this.sal=sal;
this.comm=comm;
}
//部分setter、getter略
publicvoidsetDept(Deptdept){//设置雇员所在部门
this.dept=dept;
}
publicDeptgetDept(){//取得雇员所在部门
returnthis.dept;
}
publicvoidsetMgr(Empmgr){//设置雇员领导
this.mgr=mgr;
}
publicEmpgetMgr(){//取得雇员领导
returnthis.mgr;
}
@Override
publicinthashCode(){
finalintprime=31;
intresult=1;
longtemp;
temp=Double.doubleToLongBits(comm);
result=prime*result+(int)(temp^(temp>>>32));
result=prime*result+((dept==null)?0:dept.hashCode());
result=prime*result+empno;
result=prime*result+((ename==null)?0:ename.hashCode());
result=prime*result+((job==null)?0:job.hashCode());
result=prime*result+((mgr==null)?0:mgr.hashCode());
temp=Double.doubleToLongBits(sal);
result=prime*result+(int)(temp^(temp>>>32));
returnresult;
}
@Override
publicbooleanequals(Objectobj){
if(this==obj)
returntrue;
if(obj==null)
returnfalse;
if(getClass()!=obj.getClass())
returnfalse;
Empother=(Emp)obj;
if(Double.doubleToLongBits(comm)!=Double
.doubleToLongBits(other.comm))
returnfalse;
if(dept==null){
if(other.dept!=null)
returnfalse;
}elseif(!dept.equals(other.dept))
returnfalse;
if(empno!=other.empno)
returnfalse;
if(ename==null){
if(other.ename!=null)
returnfalse;
}elseif(!ename.equals(other.ename))
returnfalse;
if(job==null){
if(other.job!=null)
returnfalse;
}elseif(!job.equals(other.job))
returnfalse;
if(mgr==null){
if(other.mgr!=null)
returnfalse;
}elseif(!mgr.equals(other.mgr))
returnfalse;
if(Double.doubleToLongBits(sal)!=Double.doubleToLongBits(other.sal))
returnfalse;
returntrue;
}
@Override
publicStringtoString(){//取得雇员信息
return"雇员编号："+this.empno+"，姓名："+this.ename+"，职位："+this.job
+"，工资："+this.sal+"，佣金："+this.comm;
}
}
classDept{//dept表映射类
privateintdeptno;
privateStringdname;
privateStringloc;
privateList<Emp>emps;//多个雇员
publicDept(){//无参构造
this.emps=newArrayList<Emp>();
}
publicDept(intdeptno,Stringdname,Stringloc){
this();//调用无参构造
this.deptno=deptno;
this.dname=dname;
this.loc=loc;
}
//部分setter、getter略
publicvoidsetEmps(List<Emp>emps){
this.emps=emps;
}
publicList<Emp>getEmps(){
returnemps;
}
@Override
publicStringtoString(){//取得部门信息
return"部门编号："+this.deptno+"，部门名称："+this.dname+"，位置："
+this.loc;
}
}
publicclassTestDemo{
publicstaticvoidmain(Stringargs[]){
//1、第一层配置关系
Deptdept=newDept(10,"ACCOUNTING","NewYrok");
Empempa=newEmp(7369,"SMITH","CLERK",800.0,0.0);
Empempb=newEmp(7566,"ALLEN","MANAGER",2450.0,0.0);
Empempc=newEmp(7839,"KING","PRESIDENT",5000.0,0.0);
empa.setMgr(empb);//设置雇员和领导的关系
empb.setMgr(empc);//设置雇员和领导的关系
empa.setDept(dept);//每个雇员属于一个部门
empb.setDept(dept);//每个雇员属于一个部门
empc.setDept(dept);//每个雇员属于一个部门
//每一个部门有多个雇员，通过对象数组表示多个雇员
dept.getEmps().add(empa);
dept.getEmps().add(empb);
dept.getEmps().add(empc);
//2、第二层取得关系
System.out.println(dept);
Iterator<Emp>iter=dept.getEmps().iterator();
while(iter.hasNext()){
Empemp=iter.next();
System.out.println(emp);
if(emp.getMgr()!=null){//有领导
System.out.println("\t"+emp.getMgr());
}
System.out.println("---------------------------------------------------");
}
}
}