引用传递的实际应用（一对多部门雇员表）

//一个部门有多个雇员，一个雇员有一个部门，一个或零个领导
//省略部分属性的setter和getter和无参构造
class Dept {
	private int deptno;
	private String dname;
	private String loc;
	private Emp emps[];//定义对象数组属性表示一个部门有多个雇员

	public Dept(int deptno, String dname, String loc) {
		this.deptno = deptno;
		this.dname = dname;
		this.loc = loc;
	}

	public void setEmps(Emp emps[]) {
		this.emps = emps;
	}
	public Emp [] getEmps() {
		return this.emps;
	}
	
	public String getInfo() {
		return "部门编号：" + this.deptno + " 部门名称: " + this.dname 
			   + " 部门位置: " + this.loc;	
	}
}

class Emp {
	private int empno;
	private String ename;
	private String job;
	private double sal;
	private double comm;
	private Dept dept;//雇员属于哪个部门
	private Emp mgr;//雇员的领导

	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 void setDept(Dept dept) {
		this.dept = dept;
	}
	public Dept getDept() {
		return this.dept;
	}
	public void setMgr(Emp mgr) {
		this.mgr = mgr;
	}
	public Emp getMgr() {
		return this.mgr;
	}

	public String getInfo() {
		return "雇员编号" + this.empno + "，雇员姓名" + this.ename 
			+"，雇员职位" + this.job + "，雇员工资" + this.sal 
			+ "，雇员佣金" + this.comm;
	}

}

public class TestDemo {
	public static void main(String args[]) {
		//产生各自独立对象
		Dept dept = new Dept(1,"西安分部","雁塔区");
		Emp ea = new Emp(7101,"james","aaa",1000.5,10);
		Emp eb = new Emp(7102,"kobe","bbb",1001.5,20);
		Emp ec = new Emp(7103,"tracy","ccc",1002.5,30);
		//设置关系数据
		//雇员与领导的关系
		ea.setMgr(eb);
		eb.setMgr(ec);
		//部门与雇员的关系
		ea.setDept(dept);
		eb.setDept(dept);
		ec.setDept(etDeptdept);
		dept.setEmps(new Emp[] {ea,eb,ec});
		//根据条件取得数据
		//根据一个雇员查询其所对应的领导信息和部门信息
		System.out.println("/t|-" + ea.getMgr().getInfo());
		System.out.println("/t|-" + ea.getDept().getInfo());
		//根据一个部门取出所有雇员信息及每个雇员对应的领导信息
		System.out.println("************************************************");
		for (int x = 0; x < dept.getEmps().length; x++) {
			System.out.println("/t|-" + dept.getEmps()[x].getInfo());
				if (dept.getEmps()[x].getMgr() != null) {
					System.out.println("/t|-" + dept.getEmps()[x].getMgr().getInfo());
				}
		}
	}
}